Question
A class of 20 students has an average age of 19 years. 5
new students join and the average becomes 17.5 years. Find the average age of the new students.Solution
Initial sum = 20 × 19 = 380 years
New average = 17.5
New total = 25
New sum = 25 × 17.5 = 437.5 years
Sum of new = 437.5 - 380 = 57.5 years
Average = 57.5 ÷ 5 = 11.5 years
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