Problem 4 · 2025 Math Kangaroo
Easy
Arithmetic & Operations
order-of-operationssum-constraint
Simona writes the numbers 2, 0, 2 and 5 in the boxes, one number per box (see picture). In what order can she write them so that the calculation gives the biggest result?
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Answer: E — 5, 2, 0, 2
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Hint 1 of 2
The third box is the one that gets subtracted, so put the smallest number there.
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Hint 2 of 2
Put the 0 in the subtracted (third) box and add everything else.
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Approach: minimise what is subtracted, maximise what is added
- The calculation is first + second minus third + fourth.
- To make it biggest, subtract the smallest number, which is 0.
- Then the other three (5, 2, 2) are all added: 5 + 2 - 0 + 2 = 9.
- The order 5, 2, 0, 2 does this, which is option E.
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