Problem 5 · 2009 Math Kangaroo
Easy
Logic & Word Problems
casework
There are three boxes in front of me: one white, one red and one green. One box holds a chocolate bar, another holds an apple, and one box is empty. The chocolate bar is in either the white box or the red box. The apple is in neither the white box nor the green box. In which box is the chocolate bar?
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Answer: A — White
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Hint 1 of 2
Start with the apple: it is in neither the white nor the green box.
Still stuck? Show hint 2 →
Hint 2 of 2
Once you place the apple, the chocolate's two options shrink to one.
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Approach: elimination
- The apple is in neither white nor green, so the apple is in the red box.
- The chocolate is in the white or the red box, but red now holds the apple.
- Therefore the chocolate is in the white box — answer A.
Mark:
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