Question
Average age of 30 students is 14 years. If 6 students
leave the class, then the average age decreases by 0.5 years. Find the average age of the students who left the class.Solution
ATQ, Total age of 30 students = 30 × 14 years = 420 years. New average age after 6 students leave = 13.5 years. Total age of 24 students = 24 × 13.5 years = 324 years. Total age of the 6 students who left = 420 − 324 years = 96 years. Average age of the 6 students who left = 96/6years = 16 years.
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