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Baskets of fruit — adult and baby monkeys
A zookeeper has 44 baskets of fruit for a troop of 58 monkeys, made up of adult monkeys and baby monkeys. Each adult monkey eats 2 baskets of fruit, and every 5 baby monkeys share 1 basket. How many adult monkeys and how many baby monkeys are there?
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The pattern behind it: Suppose and swap
Suppose everything is one kind, then swap one at a time until the total is right.
In this one. Count in fifths of a basket so nothing is a fraction, then guess "all babies" and swap babies for adults — each swap adds the same 9 fifths, so one division finds how many swaps were needed.
How to spot it
Two kinds of thing are mixed together with a known total count and a known total of something else, such as legs or sweets, and neither kind's count is given on its own.
Common mistake
Children lose track of whether a swap adds to the total or takes away from it. Compare the starting total with the target first, then swap in the direction that closes the gap.
Try one like it
Standard Bicycles and tricycles — 58 wheels A cycling club has 25 vehicles parked outside, a mix of bicycles and tricycles. Bicycles have 2 wheels and tricycles have 3 wheels…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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