Average age of family

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Average age of family

by harsh.champ » Fri Feb 19, 2010 5:57 am
The average age of a family of 5 members is 22 years. If the age of the youngest member be 10 years then what was the average age of the family at the time of the birth of the youngest member?

A. 12.5 years
B. 13 years
C. 13.5 years
D. 14 years
E. 15 years

The OA is E.
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by vijay_venky » Fri Feb 19, 2010 6:40 am
Sum of the ages =110 years now.

at the birth of the youngest member means 10 years earlier,

At that time the sum of the ages is 110-10x5 years (because of the presence of 5 members)

so the sum of the ages=60 and the average is 60/4=15(because one of the members is not there)

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by shashank.ism » Fri Feb 19, 2010 6:49 am
harsh.champ wrote:The average age of a family of 5 members is 22 years. If the age of the youngest member be 10 years then what was the average age of the family at the time of the birth of the youngest member?

A. 12.5 years
B. 13 years
C. 13.5 years
D. 14 years
E. 15 years

The OA is E.
total sum of the ages = 5x 22 =110 yrs.
so 10 years back youngest one was 0 and others were 10,10, 10 ,10 less
so total 110 - 10x5 =60
and at that time total members were only 4 so avg age of family = 60/4 =15 Ans E
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