Question

The present ages of A and B are in the ratio 7:5.ten years later,their ages will Ben the ratio 9:7.find their present ages

Answer 1

Answer:

Step-by-step explanation:

Let their present ages :

Age of A =7x

Age of B =5x

After 10 years :

Age of A = 7x + 10

Aage of B = 5x + 10

They are in ratio 9:7

So,

7x+10/5x+10 = 9/7

49x + 70= 45x + 90

49x - 45x = 90-70

4x = 20

x=5

So present age of A and B :

Aage of A =7×5=35

Aage of B = 5×5 = 25

Answer 2

Given: Present ages of A and B are in the ratio 7:5.

After 10 years

Ratio of there ages =9:7

Solution:

Let x be there present ages

7x

The easy way to do this is by using a "multiplier"

let x = the multiplier

then

7x = A's present age

and

5x = B's present age

:

Adding 10 yrs to their age produces a ratio of 9:7,

there cross multiply

7(7x+10) = 9(5x+10)

49x + 70 = 45x + 90

49x - 45x = 90 - 70

4x = 20

x = 20/4

x = 5 is the multiplier

:

Their present ages

A: 5(7) = 35 yrs

B: 5(5) = 25 yrs

Ages after 10 years

A:35+10=45

B:25+10=35

Hope it will help you