Aptitude - Average - Discussion

How the 5 is coming? Can anyone explain what is remainder?

@Ravisinh Mori, @Banita and @Ankur Mishra.

We must emphasise on the term grandparent. When we are talking about only one person (either mother or father of a grandchild) it is termed as a grandparent.

While we are talking about two people (both mother and father of a grandchild) it is termed as grandparents. Hence 2 is mentioned just to clarify that the question is talking about 2 people.

Because they have used it as a plural with plural.
(1 person=grandparent & 2 person=grandparents).

How taking grandchildren has 3? They haven't mentioned count of grandchildren.

Thanks for the answer @Rupinderjit.

How 7 came? Please explain.

I have the same concern of 11 memebers as parents includes 2 people, which Ankur mishra explained, please help me out!

Parents are grandparents means 2 people then 2 grandparents are parents means 4 nd 4 people respectively then how its here only 2 people for grandparents and parents?

Total member of the family is 11. How it 7?

Consider, Average age of grandparents is given i.e. avg = 67.

Also number of grandparents = 2.

By definition of average.

Average = total observations of all objects/total no of objects.

Let sum of individual ages of grandparents = X.

In this case,

Substituting in above formula,

67 = X/2.

Hence, X = 67x2.

And rest is average concept.

Thanks :).

It's so simple.

A = S/N.

S = A*N.

Total Sum = (2*67)+(2*35)+(3*6) = 222.

Number of people in that family = 2+2+3 = 7.

So Average=Total Sum/Num of people.

A = 222/7.

A = 31 5/7. ((7*31)+5 =222/7).