Question
Average age of 9 boys is increased by 5 years when two
of them whose age are 35 and 36 years are replaced by two new members. What is the average age of the new member?Solution
Let the sum of the age of two new members be ‘a’. Let the initial average age of boys = x After increment the average age of boys = x + 5 According to question, => 9x – 35 – 36 + a = 9(x+5) => a = 116 Average age of the new members = 116/2 = 58
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