Aptitude - Problems on Ages - Discussion

And as @newbie said, if its correct then I am failing to understand that why is 3x + 8 = 2.5 x ? Shouldn't it be 3x + 8 = 2.5 (x + 8), because even the son's age should have been added to 8 right ?

Fathers age is 3 times more than his son 4x.

But after getting full stop considering and comparing other sums I can understand like this (x+8). How we put (4x+8) in fathers age?

@Poonam And @Thara in question this given that two and half.

Means 2and half which is 2.5 and 5/2 is same equal to 2.5.

Don't get confused in 2/5 and 2.5. Because 2/5 is .4 not 2.5.

2 and a half means 2*1/2 is simplified 2*2=4, and 4+1=5 is come 5/2.

Let Ronit's age = x.

Father's age = x+3x (three times more than his son Ronit) = 4x.

After 8yrs.

Ronit's age = x+8.

Father's age = 4x+8.

But father will be two and a half times of Ronit's age so.

4x+8 = 5/2 (x+8).

x = 8.

Further after 8 years.

Ronit's age = x+8+8 = x+16.

Father's age = 4x+8+8 = 4x+16.

We know the value of x is 8 so putting value of x.

Now,

Ronit's age = x+16=8+16=24.

Father's age = 4x+16 = 4*8 +16 = 32+16 = 48.

Now we will calaulate the ratio of father's to ronit's age.

Father's age/ronit's age = 48/24 = 2.

Thus 2 is answer.

@Newbie.

You made a wrong calculation 3*16 = 48 and 52+16 = 68.

Let,

Father = X.
Ronit = Y.

1st case:
X = 3Y.

2nd case:
X+8 = Y/2.

Third case:
X+16 = Y.

2X+16 = 3Y. From 1st and second case.

Then subtract third case in it. You will get,

X=2Y.

Three times parents age of a father is equal to eight time age of his son. Eight years hence the father will twice as old as his son at that time. What are the parent ages?

Can any body solve this question?

Father can't comes to sons age i.e. Father can't come to Ronit's age. Have doubt in?

Actually the point is Ronit's father is more than 3 times. So 4x is absolutely right.