# Aptitude - Average - Discussion

Discussion Forum : Average - General Questions (Q.No. 2)
2.
A family consists of two grandparents, two parents and three grandchildren. The average age of the grandparents is 67 years, that of the parents is 35 years and that of the grandchildren is 6 years. What is the average age of the family?
 28 4 years 7
 31 5 years 7
 32 1 years 7
None of these
Explanation:
Required average
 = 67 x 2 + 35 x 2 + 6 x 3 2 + 2 + 3
 = 134 + 70 + 18 7
 = 222 7
 = 31 5 years. 7

Video Explanation: https://youtu.be/OXLnoItd0MA

Discussion:
66 comments Page 1 of 7.

In the answer how 5 comes can someone tell me.

It's remainder.

While we perform 222/7 quotent will be 31 nd remainder would be 5.

No because in question it is givven an avarage an no. Of person so answer seams to be correct an each age is being taken out.

When already the avg ages of grandparents, parents and children are given! why they have been multiplied by 2, 2 and 3 respectively?

In the answer how 6x3 came?

There are 2 grandparents of 67yrs (67*2)
2 parents of 35yrs (35*2)
3 grandchildren of 6yrs (6*3)
average = sum of total ages/no.of persons
67 x 2 + 35 x 2 + 6 x 3 divided by 2 + 2 + 3
=31 5/7
Hope that explains if not plz correct me.

Thank you swathi.

Ankur Mishra said:   1 decade ago
As you are mentioning in question that 2 grandparents are there means 4 peoples (Because grandparent consists of 2 Members)and same as in parents 2 parents means 4 person again. Then i hope here total members are 11.
Hope it is correct if not please correct me

(grandpa+granny)/2=67=134
(ma+pa)/2=35=70
(rinku+minku+chinku)/3=6=18

Now average age is(total age of all members/no of members) = 222/7(grandpa,granny,ma,pa,chinku,minku,rinku)