Problem 2 · 2024 Math Kangaroo
Easy
Logic & Word Problems
sum-constraint
Lizzy has 7 coins of one kind. She buys three fruits at the market, and each fruit has a different price. How much does the most expensive fruit cost?
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Answer: C — 4 coins
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Hint 1 of 2
Three different whole-number prices add up to 7 coins.
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Hint 2 of 2
To make the dearest fruit as big as possible, make the other two prices as small (and still different) as you can.
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Approach: maximise one value under a fixed sum with distinct prices
- The three prices are different whole numbers of coins that total 7.
- Make the two cheaper ones as small as possible: 1 and 2 coins.
- Then the most expensive is 7 − 1 − 2 = 4 coins.
- Answer: 4 coins (C).
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