Question

The ratio of the ages of father and son at present is 6: 1. After 5 years the ratio will become 7:2. Find the present age of the son?
3 years
5 years
7 years
4 years​

Answer 1

Step-by-step explanation:

Let the present age of father and son be F and S. Therefore,

F/S = 6/1

F = 6S ….(1)

and after 5 years

(F+ 5)/(S+5) = 7/2

2F + 10 = 7S + 35

2(6S) + 10 = 7S + 35 [From (1)]

12S + 10 = 7S + 35

5S = 25

S = 5 years

Answer 2

Hence, the present age of the son is 5 years (option 2).

Given,

The ratio of the ages of father and son at present is 6: 1. After 5 years the ratio will become 7:2

To find,

The present age of the son.

Solution,

We can easily solve this problem by following the given steps.

According to the question,

We have the following statements:

The ratio of the ages of father and son at present is 6: 1. After 5 years the ratio will become 7:2

Now, let's take the age of the father to be 6x years and that of his son to be x years.

So, according to the second statement:

$\frac{(6x + 5)}{(x + 5) } = \frac{7}{2}$

Using the cross multiplication method,

2(6x+5) = 7(x+5)

12x+10 = 7x+35

12x-7x = 35-10

5x = 25

x = 25/5

x = 5 years

Hence, the present age of the son is 5 years.