Question

The ages of A and B are in the ratio 7 is to 5 10 years hence the ratio of their ages will be 9 is to 7 find their present ages.

Answer 1

Answer:

Step-by-step explanation:

Let a be x and b be y

x/y=7/5

5x=7y

5x+7y=0---1)

10 years hence

x+10/y+10=9/7

7x+70=9y+90

7x-9y-20=0-----2)

Answer 2

Answer:

The Present ages are -

A = 35 years

B = 25 years

Step-by-step explanation:

Given :

Ages of A and B are in Ratio = 7 : 5

Ratio after 10 Years = 9 : 7

To Find :

Their present Ages

Solution :

Let the present Ages be -

• A as 7x
• B as 5x

$\rule{300}{1.5}$

➡ (7x + 10)/(5x + 10) = 9/7

➡ 7(7x + 10) = 9(5x + 10)

➡ 49x + 70 = 45x + 90

➡ 49x - 45x = 90 - 70

➡ 4x = 20

➡ x = 20/4

➡ x = 5

$\rule{300}{1.5}$

B's age =

➡ 5 × 5

➡ 25

$\rule{300}{1.5}$

A's age =

➡ 7 × 5

➡ 35

$\therefore$ The Present ages are -

• A = 35 years
• B = 25 years