Question
The average number of biscuits in Box Q, Box R and Box S is 30. Box Q has 50 biscuits. The number of biscuits in Box R is thrice the number of biscuits in Box S. What is the number of biscuits in Box S?
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The average number of biscuits in Box Q, Box R and Box S is 30. Box Q has 50 biscuits. The number of biscuits in Box R is thrice the number of biscuits in Box S. What is the number of biscuits in Box S?