Problem 7 · 2018 Math Kangaroo
Easy
Logic & Word Problems
careful-counting
Mike sets the table for 8 people: the fork has to lie to the left and the knife to the right of the plate. For how many people is the cutlery set correctly?
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Answer: A — 5
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Hint 1 of 2
Sit in each chair in turn; the setting is right only if the fork is on your left hand and the knife on your right hand.
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Hint 2 of 2
Remember that someone sitting on the far side of the table faces you, so their left and right are flipped from yours.
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Approach: stand in each person's place and check fork-on-left, knife-on-right from their seat
- Picture yourself sitting in each of the 8 chairs, facing the plate.
- From that seat the fork must be by your left hand and the knife by your right hand — tick the places that match.
- Exactly five places pass the test, so the cutlery is set correctly for 5 people, answer A.
Mark:
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