Question
Sum of ages of 65 students is 1300 years. The average
age of 25 of them is 16 years and the average age of another 20 of them is 14 years. Find the average age of the remaining students.Solution
Given, sum of age of 65 students = 1300 years
Sum of age of 25 students = 25 × 16 = 400 years
Sum of age of another 20 students = 20 × 14 = 280 years
Remaining number of students = 65 – 25 – 20 = 20
Average age of remaining 20 students = {(1300 – 400 – 280)/20} = (620/20) = 31 years
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