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A common quick fix is to tell a student to add dollar signs to the denominator. Sometimes that fixes the particular calculation. Sometimes it creates the next mistake. The meaningful starting question is: “Does this calculation use one shared whole, or does each row have its own whole?” The answer determines which references should stay fixed and which should follow the row.

Imagine four activities sharing a budget of 200 units. Activity A uses 30 units. Its share is 30 divided by 200, which is 0.15 or 15%. If the next row records Activity B using 50 units, its share is 50 divided by the same 200, or 25%. The numerator changes because the activity changes. The denominator stays because both shares refer to the same budget.

Now consider two tests. A student scores 18 out of 24 on one test and 21 out of 30 on another. The percentages are 75% and 70%. Each row has a different whole. Fixing every denominator to 24 would make the second calculation 21 divided by 24, or 87.5%, which answers a different question. A mechanical instruction to lock the denominator cannot replace understanding the data.

Ask your child to finish this sentence before touching the spreadsheet: “This percentage tells me how much of ___ is represented by ___.” For the budget example, the blanks are the shared budget and one activity’s allocation. For the test example, they are the available marks on that test and the marks earned on that test. The wording keeps the calculation connected to its meaning.

Once the relationship is clear, the references become easier to choose. A shared total needs a stable address when copied down. Row-specific earned marks and available marks should both follow their own row. The formula design serves the mathematical relationship.

This is the first parent decision. If the child cannot name the whole, work on percentages before teaching reference shortcuts. If they can name it and calculate independently, investigate how the spreadsheet represents the relationship. Both difficulties are teachable, but they need different practice.

Give the child two paper questions without a spreadsheet. “What percentage of 200 is 30?” and “What percentage is 21 out of 30?” Suitable answers are 15% and 70%. Ask them to explain the denominator in each calculation. Correct answers without an explanation may come from a remembered procedure, so listen for the relationship as well as the number.

Next give two formula descriptions. In the first, amounts are in cells A2 and A3, and one shared total is in B1. In the second, earned marks are in A2 and A3, with the corresponding available marks in B2 and B3. Ask which denominators should be used in the second row. The answers are B1 for the shared total and B3 for the second test.

Then show a copied formula. Suppose C2 contains =A2/B1 and is copied down one row to C3. In a spreadsheet using ordinary relative references, it becomes =A3/B2. Ask the learner what changed and whether that change matches the budget relationship. A child who can calculate 50 divided by 200 but accepts B2 without checking has a reference reasoning difficulty, not necessarily a percentage difficulty.

Finally show =A2/$B$1 copied down to =A3/$B$1. Ask why the fixed reference helps this particular task. The answer should mention the shared total in B1. “Because dollar signs make formulas correct” is not enough. Change the task to test scores with row-specific totals and ask whether the same fixed denominator is still suitable.

Record one precise diagnosis. Perhaps the learner chooses the wrong whole even on paper. Perhaps they understand the percentage but do not inspect copied references. Perhaps they inspect references correctly but confuse 0.15 with 0.15%. Each finding suggests a different next lesson.

A parent need not become a spreadsheet specialist to run this conversation. The purpose is to see the child’s reasoning under a small change. If the task grows complicated, return to two rows and one relationship. That small example usually reveals more than a large worksheet full of formulas the child has already copied.

A relative reference describes a cell in relation to the formula’s position. Microsoft documents that ordinary references change when a formula is copied to another position. For this guide, consider copying down by one row. A2 becomes A3, and B1 becomes B2. The column letters stay the same because the copy moved down rather than across.

That behaviour is useful when each row contains another instance of the same relationship. If C2 calculates =A2/B2 for the first test, copying it down gives =A3/B3 for the second. The formula still divides earned marks by the corresponding available marks. The addresses change, but the intended relationship stays the same.

The same behaviour causes trouble when a cell has a different role. In the shared budget example, B1 is a common total, not the available total for the first activity row. When =A2/B1 becomes =A3/B2, the formula has moved away from that shared total. The spreadsheet has followed its copying rule; the student’s formula did not express the intended stable relationship.

Ask the child to predict the next formula before using a fill handle. If D4 contains =B4/C4 and is copied down one row, the predicted formula is =B5/C5. If it is copied across one column instead, the ordinary references become C4 and D4. Teach one direction at a time until the learner can explain both. A diagonal copy changes the relevant row and column positions together.

Do not confuse copying a formula with every possible operation on a spreadsheet. Moving cells, inserting rows and other edits can involve additional behaviour. This lesson is about ordinary copied formulas and their reference types. If a different operation caused the problem, inspect that operation rather than assuming the same example covers it.

The useful learning sentence is: “A relative reference moves with the copied formula’s position.” The useful checking question is: “Should this part of the mathematical relationship move with that position?” When the child can answer both, reference rules stop being isolated computer facts and become a way to preserve the intended calculation.

Build the shared budget example on paper first. Put 200 in B1. Put the activity amounts 30, 50, 40 and 80 in A2 through A5. Each row’s percentage uses the same whole. In C2, the formula =A2/$B$1 expresses that relationship: A2 follows the activity row, while B1 stays fixed when the formula is copied.

Copied down to C3, it becomes =A3/$B$1. With A3 equal to 50 and B1 equal to 200, the value is 0.25, displayed as 25% if the cell uses percentage formatting. The next two shares are 20% and 40%. Together the four allocations total 200 and the four shares total 100%. Those checks fit this example because the listed allocations cover the entire stated budget exactly once.

Compare the unfixed formula =A2/B1. Its next copy is =A3/B2. If B2 is empty, the result may be an error rather than the expected share. If B2 contains an unrelated number, the result may be a convincing looking percentage of the wrong whole. A visible error is often easier to notice than a plausible but irrelevant result.

Ask the child to explain both dollar signs in $B$1. The column B and row 1 are fixed. Copying down changes the row position of the formula but keeps the reference on B1. Copying across also keeps B1 fixed. In this example, that is useful because B1 is the single common total regardless of the activity row.

Now ask why A2 is not fixed. Each copied row should use its own activity amount. If the child changes it to $A$2 as well, every row uses the first amount and displays 15%. The repeated value looks orderly but fails to represent the other activities. This comparison teaches that fixing more references does not automatically improve correctness.

The parent can summarise the decision in ordinary words: “Keep the shared whole; follow the changing part.” That sentence belongs to this shared-total task. It should not become a universal denominator rule. The next chapter changes the relationship so the learner has to choose again.

Use a table of three invented tests. Test A records 18 earned marks out of 24 available. Test B records 21 out of 30. Test C records 16 out of 20. Put earned marks in column A and available marks in column B, beginning at row 2. The percentages are 75%, 70% and 80%.

The formula in C2 is =A2/B2. Copied down, it becomes =A3/B3 and then =A4/B4. Both references should follow the row because each earned mark must be paired with the available marks for that same test. The changing denominator is not a fault. It is necessary to keep the meaning correct.

Contrast this with =A2/$B$2. The second row would divide 21 by 24, giving 87.5%. The third would divide 16 by 24, giving approximately 66.67% when displayed to two decimal places. Those values are valid calculations of the supplied numbers, but they are not the percentages earned on Tests B and C. Mathematics includes selecting relevant quantities, not only carrying out division accurately.

Ask the learner to identify the smallest repair. The numerator should stay relative, and the denominator should become relative too. They do not need to rebuild the entire file or lock another cell. A repair should address the actual dependency that contradicts the relationship.

Then change the numbers so all three tests happen to be out of 20. The wrong fixed-denominator design might now produce the correct results for the current rows. Ask whether that proves the design is suitable for a future test out of 30. It does not. A formula can be accidentally correct for one data set and fail when the intended row-specific whole changes.

This is why a good practice task varies the totals. Equal denominators are easy for a beginning example, but they hide the distinction the child needs to learn. A tutor should eventually include a row with a different whole and ask the student to explain the references. Independent explanation reveals whether the child understands the design rather than merely recognising a familiar formula.

A copied formula can be correct while the display confuses the learner. The fraction 30 divided by 200 equals 0.15. Percentage formatting displays that fraction as 15%. The two forms express the same proportion. The spreadsheet has not changed the underlying mathematical relationship merely by presenting it in percentage form.

A common error is to use =(A2/B1)*100 and then apply percentage formatting. With 30 and 200, the formula returns 15. Percentage formatting displays that as 1500%. The multiplication and the display convention have both introduced the factor of 100. The correct choice depends on the intended representation: use the fraction with percentage formatting, or calculate the percentage number explicitly and label it consistently without converting it again through percentage formatting.

For a beginner, the simplest coherent route is =A2/$B$1 with percentage formatting for the shared budget. Ask the child what value the formula calculates and what the display shows. They should be able to say “0.15, shown as 15%.” This separates calculation from presentation without requiring a long software lesson.

Try another example. Twelve out of forty is 0.3, or 30%. A cell containing the number 30 and displayed as a percentage represents 3000%, not the intended 30%. A cell containing 0.3 and displayed as a percentage shows the intended proportion. If the child types “30%” directly, a spreadsheet may store the proportion accordingly; check the application’s behaviour rather than assuming every input method is identical.

The diagnostic question is: “Did the relationship change, or did the representation change?” If the formula points to the wrong denominator, the relationship is wrong. If the relationship is right but the display is misunderstood, the lesson concerns representation. Fixing dollar signs will not solve a double conversion to percentage.

At home, write a three-column note: fraction, decimal and percentage. For 3 out of 20, the entries are 3/20, 0.15 and 15%. Match the spreadsheet result to that note. A student who can move between these forms has a reliable independent check on a display that initially looks surprising.

The article title uses “changes” to describe an unexpected spreadsheet result. A mathematical percentage change is a separate relationship. Teach that difference explicitly. A share asks how much of a whole a part represents. Percentage change asks how a quantity differs from its original value, relative to that original value.

Suppose an invented quantity rises from 80 to 100. The increase is 20. The percentage increase is 20 divided by 80, which is 0.25 or 25%. Dividing 20 by 100 gives 20%, but that uses the new value as the denominator and answers a different comparison. The original value matters because it is the starting reference for the stated change.

A spreadsheet table might put old values in A2 and new values in B2. A suitable signed percentage change formula is =(B2-A2)/A2. Copied down to the next row, it becomes =(B3-A3)/A3. Both the original and new values follow their own row because each row describes another comparison. Applying percentage formatting displays the result as a percentage.

For a second row, let the original value be 50 and the new value be 40. The formula returns -0.2, or -20%. The sign indicates a decrease under this convention. If the question asks for the size of the percentage decrease as a positive amount, explain that wording and calculate 10 divided by 50, or 20% decrease. Do not erase the sign without knowing what the task asks.

Ask the learner to label every quantity: original, new and difference. A student may know the reference rules perfectly but still divide by the wrong base. That is a mathematical interpretation problem. The appropriate repair begins with the question’s meaning and then updates the formula.

Avoid turning this lesson into financial advice or forecasting. The numbers are teaching quantities. The useful skill is choosing the base for a comparison and maintaining it when the calculation is copied. A tidy percentage column cannot tell a parent whether the student understands shares, increases and decreases unless the learner can explain what each denominator means.

An absolute reference fixes both the column and row. A mixed reference fixes one and allows the other to change. In $B1, the column B stays fixed while the row can change. In B$1, row 1 stays fixed while the column can change. These forms are useful, but they should enter the lesson only after the child understands why a reference needs to move in one direction and stay in another.

Consider a two-dimensional teaching table. Each row contains a quantity in column A, and each column has a comparison whole in row 1. The table is designed to calculate each row quantity as a share of each column whole. This is a constructed mathematical exercise, not a claim about the best layout for every spreadsheet.

At B2, use =$A2/B$1. The numerator must stay in column A as the formula is copied across, but follow the row when copied down. The denominator must stay in row 1 when copied down, but follow the column when copied across. Copying one column right gives =$A2/C$1. Copying one row down from the original gives =$A3/B$1.

Use numbers to make the meaning visible. Put 30 in A2 and 50 in A3. Put 100 in B1 and 200 in C1. The four shares are 30%, 15%, 50% and 25%, respectively. Ask the child to calculate them by hand and then explain which cell each copied formula should use. The formulas should express the same four relationships.

If the learner becomes overwhelmed, return to the one-dimensional shared budget example. Mixed references are an extension, not a badge of mathematical sophistication. The parent should not interpret difficulty with a new spreadsheet feature as proof of a broad Mathematics weakness.

A useful transfer question is: “Which direction should each reference follow?” That question explains the dollar signs better than memorising four patterns in isolation. After the child answers in words, they can choose the corresponding notation. The notation then records an understood decision instead of becoming another rule to copy without meaning.

A large spreadsheet can repeat one incorrect dependency many times. The efficient habit is to inspect the first copied row before filling the rest. This is not a promise that two rows prove every calculation is correct. It is a practical early check that catches many reference mistakes before they spread through a table.

In the shared budget example, read C2 and C3 as relationships. C2 should use A2 and B1. C3 should use A3 and B1. If C3 uses B2, stop and repair the formula design. Do not judge it only by whether the displayed percentage looks reasonable. Read the referenced values and ask whether they belong to the intended part and whole.

Then inspect a row farther down. This confirms that the same pattern continues and can reveal an exceptional row with a different structure. For example, a subtotal row should not automatically receive the same calculation as an ordinary activity row if doing so would double count an allocation. The table’s meaning still governs what belongs in each row.

Ask the child to predict one formula before checking it. “If I copy this to row 5, what should the formula be?” In the shared-total case, =A5/$B$1 is the intended answer. In the test-score case, =A5/B5 is appropriate if row 5 contains another test’s earned and available marks. Prediction shows understanding more clearly than noticing a problem only after an error message appears.

Keep a brief audit note: intended relationship, first formula, first copy and independent numerical check. This note helps the child explain a repair later. It also gives a parent or tutor a compact evidence set without sharing a whole personal file or unrelated data.

Once the design is correct, the child can fill the range needed for the task and check its boundaries. The learning objective is an orderly method: define, predict, copy, inspect and calculate independently. The spreadsheet handles repeated arithmetic, while the student remains responsible for ensuring the repeated operation is the one the question requires.

An error message draws attention, but a plausible number can slip through. Suppose 50 is divided by an unrelated 100 after a reference moves. The result is 50%. If the intended whole was 200, the correct share was 25%. Both percentages look ordinary. Only the meaning and an independent calculation reveal which one answers the question.

Choose a check that uses a simple relationship. In a shared total of 200, an amount of 100 must be 50%, and an amount of 50 must be 25%. If the spreadsheet shows another value, inspect the formula and referenced inputs. A known benchmark makes the error easier to recognise without relying on a vague feeling that the column looks wrong.

For row-specific test totals, choose one row with a different denominator. Twenty out of twenty-five is 80%. If every row was accidentally locked to a total of twenty, that row would show 100%. The deliberately varied denominator is informative because it tests the particular dependency that might be wrong.

For percentage change, use a doubling example. A quantity rising from 40 to 80 increases by 100%, because the increase equals the original 40. A formula dividing the increase by the new 80 returns 50%. The benchmark exposes the wrong base clearly. It is more diagnostic than two values so close that both mistaken and correct answers appear unremarkable.

Ask the learner to explain why the chosen check is useful. “I know the answer already” is part of the reason. The stronger reason is that the example distinguishes two possible formula designs. A good check is selected to reveal an error, not merely to produce another calculation resembling the first one.

Do not depend only on the spreadsheet’s total or on matching the teacher’s displayed answer. Use paper arithmetic and labels independently. If the hand calculation and spreadsheet disagree, trace the quantities before changing the software. The child may discover a wrong input, a wrong reference, a wrong base or a display misunderstanding. Each finding deserves the repair that matches it.

Parents often tell children that percentages should add to 100%. That is useful in a particular kind of table: categories that divide the same whole completely, with no overlap and no missing part. It is not a universal test of a percentage column. Different percentages may refer to different wholes or to changes rather than shares.

Return to the budget example. The amounts 30, 50, 40 and 80 total 200. Each is divided by the same 200. Their shares, 15%, 25%, 20% and 40%, total 100%. The check fits because every listed activity accounts for part of the stated whole and the allocations cover it exactly once.

Now consider the three test percentages 75%, 70% and 80%. Their sum is 225%, but that does not show an error. They refer to three separate tests, each with its own available marks. They are not pieces of one shared whole. The child must understand the relationships before deciding whether addition is meaningful.

Suppose a survey allows a respondent to choose more than one activity. Shares of respondents selecting each activity may total more than 100%, because the categories overlap. In another invented table, only two categories out of five are shown; their shares need not total 100% because the table is incomplete. The captions matter as much as the arithmetic.

Even in a complete non-overlapping table, displayed rounded percentages may sum slightly above or below 100%. Distinguish rounding of the display from an incorrect relationship. Inspect the underlying fractions and the total coverage before forcing one cell to make the displayed sum exactly 100%. Altering a result simply to improve appearance can hide the real calculation.

A parent can ask, “What does each percentage use as its whole, and do these rows divide that same whole?” If the child answers clearly, they can choose an appropriate check. The goal is not to abandon convenient checks. It is to know why a check applies, so it gives reliable evidence instead of becoming another automatic rule that creates confusion in a different task.

A denominator of zero requires attention to the relationship. A percentage defined as part divided by whole cannot be calculated by ordinary division when the whole is zero. A blank cell raises a different question: is the relevant total missing, intentionally absent or represented elsewhere? The child should not treat both situations as an ordinary percentage of zero.

Use an invented test record. The earned marks are 0 and available marks are 20. The percentage is 0 divided by 20, or 0%. That is a valid share: no marks were earned from a nonzero available total. Now change the available marks to 0. The expression 0 divided by 0 does not establish the same percentage. The relationship needs interpretation rather than an automatic zero answer.

For percentage change, a quantity moving from 0 to 10 cannot use the ordinary change formula with zero as its original denominator. The increase is 10 units, but that alone does not provide a finite percentage increase by dividing by the original zero. A student should report the absolute change and the limitation appropriate to the task rather than fabricate a percentage.

If a copied formula suddenly encounters an empty denominator cell, inspect why it is empty. In the shared budget example, that may be evidence that the denominator reference moved away from B1. Replacing the resulting error with a blank display would make the table look cleaner while leaving the dependency wrong. Diagnose before deciding how missing data should be presented.

Do not teach an error-hiding function as the first repair. Such functions can have legitimate uses, but they do not prove that the mathematical relationship is correct. A learner needs to understand whether there is missing input, an invalid denominator or a copied-reference mistake. Those cases call for different actions.

The parent decision is to slow down at the first unexplained error. Ask the child to name the intended whole and find its cell. If it is genuinely unavailable, record that limitation. If the formula points to the wrong place, repair the reference. Accurate handling of an unknown is better Mathematics than a confident percentage produced merely to fill every row.

A spreadsheet surprise can make a capable child feel that all their Mathematics is unreliable. A parent can reduce that worry by identifying the actual difficulty. If the learner selects the correct whole and calculates percentages on paper, the next lesson may be a small reference exercise. If they choose the wrong whole before using the spreadsheet, the lesson should begin with the meaning of the percentage.

Bring a compact example to a potential Secondary 2 Mathematics tutor. Include the question, two rows of invented or appropriately shared data, the original formula, the first copied formula and the child’s hand calculation. Add the child’s explanation of the denominator. This evidence reveals more than a screenshot of a finished column, because it shows the intended relationship and the transformation that went wrong.

Ask what the tutor would teach first and how they would check independent understanding. A useful plan might compare shared-total shares with row-specific test percentages, then ask the child to predict a copied formula in a changed task. That check makes the learner explain the choice of reference instead of reproducing one demonstrated answer.

Match the lesson to the student’s actual subject level and school sequence. Singapore’s secondary Mathematics provision includes different subject levels under Full Subject-Based Banding. Do not assume that every Secondary 2 student follows an identical task sequence, or that a spreadsheet extension is a prescribed lesson for every class. The current MOE syllabus materials and school work provide the scope.

SEAB’s current information states that the Secondary Education Certificate is introduced from the 2027 graduating cohort, bringing the national secondary examinations together with subjects taken at G1, G2 or G3. Checked on 9 October 2026, this transition is a reason to follow the student’s actual cohort and subject requirements. It is not permission to infer examination tool rules from a home spreadsheet activity.

Use existing eduKatePunggol level and subject pages for an enquiry, and confirm practical arrangements directly. This article establishes no timetable, price, location, result or available place. It helps a parent describe a learning need clearly so any proposed teaching can be assessed on its relevance to the child’s work.

A useful home session can contain three small tasks rather than one long copied column. Begin with a shared total. Give amounts of 12 and 18 from a total of 60. The shares are 20% and 30%. Ask the child to write the relationship, choose the shared denominator and predict the next copied formula. Keep the table to two rows so the reasoning stays visible.

Next use row-specific totals. Give 12 out of 15 and 18 out of 24. The percentages are 80% and 75%. The child should explain why the denominators now follow their respective rows. If they reuse the locked shared denominator from the first task, ask which whole the second row requires. The contrast is the lesson; it is not a trick.

Finally use percentage change. Give an original value of 60 and a new value of 75. The increase is 15, and 15 divided by 60 gives 25%. Ask which value provides the base and why. This task checks whether the child recognises a different relationship rather than applying “part over total” vaguely to whichever two numbers are nearby.

For each task, ask for a paper calculation before a formula. After one copy, ask for a prediction and an inspection. If the child makes a mistake, preserve the original and write the corrected formula beside it with a short reason. “Fixed the shared total” is a useful reason; “changed it until the answer looked right” is not.

Stop after the learner can explain the relevant distinction independently, or when attention fades. A long article offers several routes for different needs; it does not require the parent to teach every chapter in one sitting. A calm, successful comparison is better than an exhausted tour of every spreadsheet feature.

At the next session, change the numbers and the layout slightly while keeping the relationship recognisable. If the child can choose the references again, the understanding is becoming more flexible. Note the specific success without predicting a grade. “Could distinguish a shared whole from a row-specific whole” describes real learning and gives the next practice a sensible starting point.

“Should my child always lock the denominator?” No. Lock a reference when the relationship requires that referenced cell to stay fixed during the intended copy. A shared budget total is one example. Separate test totals should usually follow their corresponding rows. Ask what the denominator represents before choosing its reference type.

“Why does the spreadsheet give a sensible percentage that is wrong?” The software may be carrying out valid arithmetic on the cells the formula names. If those cells do not represent the intended part and whole, the number answers a different question. A plausible result is a reason to check meaning, not evidence that the formula design is correct.

“Does adding dollar signs change the percentage formula?” It changes how the reference behaves when copied. It does not redefine what a percentage means. In the shared-total example, it keeps the denominator on the intended whole. In a row-specific example, inappropriate fixing can make the mathematical relationship wrong in later rows.

“Why is 0.25 shown as 25%?” A percentage expresses a proportion per hundred. The decimal 0.25 represents one quarter, which is 25%. Percentage formatting shows that representation. Multiplying the fraction by 100 and also applying percentage formatting can produce a double conversion. Check calculation and display separately.

“Should every percentage column add to 100%?” Only when the rows are complete, non-overlapping parts of the same whole, subject to rounding of the displayed values. Test scores, overlapping survey selections and percentage changes do not automatically have that property. Choose the check that matches the table’s meaning.

“Is this an examination spreadsheet lesson?” This guide uses spreadsheets as a learning extension for percentages and relationships. It does not establish national examination software permissions, required tools or a universal Secondary 2 spreadsheet unit. Follow the current official information and the student’s school instructions for the actual assessment.

“What should I tell a tutor?” State the observed difficulty precisely. “They calculate 50 out of 200 correctly on paper, but accept the denominator moving after a copy” identifies a different need from “They divide by the new value when finding percentage change.” A focused description helps the tutor plan a focused first lesson.

Give the learner this invented table description. Rows 2 and 3 contain amounts of 24 and 36 in column A. One shared total of 120 is in B1. Ask for the two percentages and a suitable formula in C2 that can be copied down. The answers are 20% and 30%, with =A2/$B$1 under the layout described.

Ask them to predict C3 without dragging. The intended formula is =A3/$B$1. Then ask why A changes and B1 does not. The explanation should identify the changing row amount and the shared whole. If the learner says only “because of the dollar signs”, ask what mathematical decision those signs represent.

Now replace the shared total with row-specific totals. Put 40 in B2 and 60 in B3, keeping the amounts 24 and 36. The percentages are now both 60%. A suitable formula in C2 is =A2/B2, copied down to =A3/B3. The repeated answers are correct here because each part represents the same proportion of its own whole.

This contrast is valuable. Earlier, repeated 15% values could reveal an incorrectly fixed numerator. Here repeated 60% values are legitimate. The child should not judge formula correctness from whether a column repeats or varies. They must inspect the relationship, inputs and references. Appearance alone cannot distinguish the two cases.

For a final question, change an original quantity from 120 to 150. Ask for the percentage increase. The increase is 30, and 30 divided by the original 120 gives 25%. This checks whether the learner switches from a share task to a change task and chooses the correct base, rather than copying the last formula mechanically.

Record one independent success and one remaining need. Perhaps the child now chooses a shared denominator correctly but still needs help with percentage display. That is a useful next step, not a reason to restart every topic. Return to the existing Mathematics hub for broader reading, and use the child’s demonstrated thinking to choose the next practice. The spreadsheet becomes a tool for expressing understood relationships, while the learner keeps responsibility for what the numbers mean.