P4–P5–P6 Factors and multiples
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PSLE 2025 — Sam and ava
Sam and Ava have the same amount of money. The amount each had was less than $40. Ava bought some pillows at $8 each and had $3 left. Sam bought some towels at $5 each and had $7 left. How many towels did Sam buy?
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The pattern behind it: Factors and multiples
The answer comes from how the numbers divide, not from a bar model.
In this one. When each person's money is "a multiple of something, plus a leftover", list every amount that fits each rule up to the limit and take the one value that appears on both lists.
How to spot it
Words like 'as many teams as possible', 'equally divided with none left over', or 'has exactly this many factors' appear, without any ratio or fraction in sight.
Common mistake
Children reach for the lowest common multiple when the question needs the highest common factor, or try to list every factor of a number by hand instead of building it from its prime factors.
Try one like it
Standard PSLE 2023 — Teams 72 girls 60 boys Mrs Wong wanted to divide 72 girls and 60 boys equally into as many teams as possible, with every team having the same number of g…The 33 problem patterns
All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.
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