Problem 3 · 2018 Math Kangaroo
Easy
Arithmetic & Operations
total-then-divide
Which beetle has to fly away so that the beetles that are left have 20 dots altogether?
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Answer: B — Beetle with 7 dots
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Hint 1 of 3
Count the dots on every beetle and add them all together first.
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Hint 2 of 3
You have too many dots — the beetle that flies off should carry away the extra ones.
Still stuck? Show hint 3 →
Hint 3 of 3
How many dots over 20 do you have? Look for the beetle with exactly that many.
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Approach: find how many dots are extra, then spot that beetle
- Count the dots on the five beetles: 5, 7, 5, 6 and 4. Adding them gives 27 dots in all.
- You want only 20 dots left, but you have 27 — that is 7 too many.
- So the beetle that flies away must take 7 dots with it: the beetle with 7 dots.
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