Question
In a batch of 36 students, the average age is 25 years.
Later, 6 new students join the batch and the average age of the entire class drops by 1.5 years. What is the average age of the new students?Solution
Initial sum = 36 × 25 = 900 years
New average = 23.5
New total = 42
New sum = 42 × 23.5 = 987 years
New students' sum = 987 - 900 = 87 years
Average = 87 ÷ 6 = 14.5 years
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