Question
The average number of puffs in Box W, Box X and Box Y is 42. Box W has 21 puffs. The number of puffs in Box X is four times the number of puffs in Box Y. What is the number of puffs in Box Y?
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The average number of puffs in Box W, Box X and Box Y is 42. Box W has 21 puffs. The number of puffs in Box X is four times the number of puffs in Box Y. What is the number of puffs in Box Y?