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3 yr ago, the average age of a family of 5 members was 17 yr. Even after a birth of a child, the average is same today. Find out the age of the child

A) 1 yr
B) 3 yr
C) 2.5 yr
D) 2 yr

Correct Answer:




D) 2 yr

Description for Correct answer:
3 years ago total age of 5 members of the family = 17 X 5 = 85 year

Present age of all the members of the family = 85 + 3 X 5 = 100 yr

Let the age of the child = x yr.

Present average age of family = \( \large\frac{100 + x}{6} \)

At present total number of members = 5 +1 = 6

\( \large 17 = \frac{100 + x}{6} = 102 = 100 + x\)

So x = 2 yr.

Part of solved Average questions and answers : >> Aptitude >> Average

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