Question
The average number of tarts in Box X, Box Y and Box Z is 30. Box X has 30 tarts. The number of tarts in Box Y is thrice the number of tarts in Box Z. What is the number of tarts in Box Z?
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The average number of tarts in Box X, Box Y and Box Z is 30. Box X has 30 tarts. The number of tarts in Box Y is thrice the number of tarts in Box Z. What is the number of tarts in Box Z?