Question
Average age of 16 students is 18 years. If 4 students
leave the class, then the average age decreases by 1.5 years. Find the average age of the students who left the class.Solution
ATQ, Total age of 16 students = 16×18 years = 288 years. New average age after 4 students leave = 16.5 years. Total age of 12 students = 12×16.5 years = 198 years. Total age of the 4 students who left = 288−198 years = 90 years Average age of the 4 students who left = 90/4years = 22.5 years
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