Aptitude - Problems on Ages - Discussion

X, X+3, X+6, X+9, X+12=50
5X = 50-30.
5X = 20.
X = 4.

Guys its very simple.

5 children s sum is 50;

So 50/5=10;

Will get 10 as the middle number, it means the age of 3rd child is 10yrs, so each child born 3 yrs diff, so 10 is middle means,

4 (+3yr gap) 7 (+3yr gap) 10 (middle child(+3yr gap)) 13 (+3yr gap) 16...

So youngest child age is 4.

There are 5 children. Each is borned in 3 years gap.
It means age of childrens.

Let assume age of first children is x year.

Hence, age.

1st child is : x.
2nd : x+3.

3rd : x+6 i.e.(x+3+3) (simply 3rd child is born after 3 years from the birth of 2nd child).

Similarly,
4th child age : x+9.
5th child age is: x+12.

If we add all children age together.

x+ (x+3) + (x+6) + (x+9) + (x+12) = 50 (it is given in question The sum of ages of 5 children born at the intervals of 3 years each is 50 years. ).

By adding all x together and all numbers it comes.

5x + 30 = 50.
5x = 20(50-30).
x = 4(20/5).

Hence the age of all kids.

1st: x = 4 year.
2nd: x+3 = 4+3 = 7 year.
3rd: x+6 = 4+6 = 10 year.
4th: x+9 = 4+9 = 13 year.
5th: x+12 = 4+12 = 16 year.

x+3+x+6+x+9+x+12+x = 50.

5x+30 = 50.
5x = 50-30.

5x = 20.
x = 20/5.

x = 4.

What is the age of the middle child?

Let us assume that:

a, b, c, d, e are five childs to him.

Let,

a = x;

b = x+3;

c = x+6;

d = x+9;

e = x+12;

Then,

x+(x+3)+(x+6)+(x+9)+(x+12) = 50;

Therefore,

5x = 20;

x = 4.

So,

a = 4.

Youngest one.

x+ (x+3) + (x+6) + (x+9) + (x+12) =50.

Add all the x is 5x.

And all the numbers is 30.

Then,

5x+30 = 50.

5x = 50 - 30.

5x = 20.

x = 20/5.

x = 4.

So the age of the youngest child is 4.

(x+2),(x+4),(x+6),(x+8),(x+10).
Total: x+2+x+4+x+6+x+8+x+10 = 50.

5x+30=50
5x=20
x=4.

X+12+x+9+x+6+x+3+x=50.

5x+30=50.

(x+6) =10.

X=4.

@Sylivia.

Look the options and add 3 to the 1st option and we can find it out i.e., 4+3=7.

Then 7+3=10 actually dat is de middle age: 10+3=13, 13+3=16.

Good luck.