A Crawford family choosing Primary 6 Mathematics tuition is choosing the conditions around the lesson as well as its time. A weekday may provide timely help; a weekend may offer room for a quieter before-and-after explanation.
Transfer-ratio questions reveal a useful learning need. Moving objects between two collections changes both individual counts but leaves their combined total unchanged.
Start with that conserved total, then choose a routine with room for independent practice. Confirm the actual venue and current availability, and include food, travel and recovery in the plan.
eduKateSG · Crawford · Mathematics
Choose a useful learning rhythm
Identify the learning need · Consider weekdays · Consider weekends · Try the worked example · Review your next step
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Ask your child what happens when cards move from one person to another without entering or leaving the pair. One count falls, another rises and the total stays fixed.
A pupil may compare the first terms of two ratios without checking their total units. The unit size must be consistent before a difference can represent the transfer.
A labelled model can help. If the before-and-after ratios have the same total unit count, the conserved total allows their unit sizes to be compared directly.
A weekday lesson may revisit a school problem while your child remembers the attempted model. The teacher can identify whether the transfer or unit comparison was misread.
Allow food and a pause after school and travel. A tired pupil may manipulate ratio terms without explaining which actual amount stays unchanged.
On another day, ask for the total units in each ratio before calculating. This short task can test the setup.
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A weekend session may provide room to compare the starting counts, transfer and final counts. A model can show that the transferred cards belong to both changes.
Keep the learning goal focused and finish with a fresh independent question. More available time does not require several unrelated ratio methods together.
Plan a brief weekday revisit with changed ratios. The child should identify the conserved quantity again rather than remember the previous subtraction.
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Alicia and Tricia have cards in the ratio 4:1. Alicia gives eighteen cards to Tricia, after which their ratio is 2:3. Find their initial counts. Assume there are no other changes.
Both ratios contain five total units. Since the combined card count stays unchanged, the unit size is the same in both states.
Alicia’s count falls from four units to two units. The two-unit decrease represents eighteen cards, so one unit is nine cards.
Initially Alicia has 36 cards and Tricia nine. Afterwards their counts are 18 and 27.
Check both ratios: 36:9 is 4:1, and 18:27 is 2:3. The total is 45 cards before and after, and the transfer is exactly eighteen.
For a fresh attempt, the starting ratio is 5:2 and the final ratio after a transfer is 3:4. Both contain seven units. If twelve cards are transferred from the first person to the second, two units represent twelve.
One unit is six, giving initial counts of 30 and 12 and final counts of 18 and 24. When ratio totals differ, they must be aligned appropriately before this direct comparison can be used.
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In a three-pupil group, every child can explain why the total remains unchanged. The teacher can hear whether the unit comparison is understood or merely copied.
After a shared example, pupils need separate fresh attempts. Each child should check both ratios, the transfer and the conserved total independently.
Ask about group matching and individual feedback. Confirm the actual teaching venue, available sessions and travel arrangements.
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After several lessons, use another transfer question. Can your child identify the invariant and verify all the stated conditions?
If the method works only with familiar ratios, return to the labelled quantities. If the relationship is secure, address arithmetic slips separately.
Match practice to taught topics, the school’s current scope and the appropriate examination specification. These examples are original teaching illustrations, not official assessment questions.
Bring recent work and your family’s workable times to a diagnostic discussion through the eduKate enquiry page. Choose the routine after the starting point is clear.
References and next steps
Official examination reference: SEAB PSLE formats examined in 2026, including separate Standard and Foundation Mathematics specifications. Use the document for the pupil’s examination year and level, and the school’s current assessment instructions. Worked examples are original teaching illustrations; suggested routines are practical options rather than official assessment requirements.
Mathematics Learning Hub · Discuss your child’s learning needs with eduKate