Question

if the present ages of a&b are in the ratio of 9:4 and after 7 years there ages are in the ratio of5:3 then find there present age​

Answer 1

Answer:

Let the ratio be 9x : 4x.

After 7 years,

Age of A = 9x + 7

Age of B = 4x + 7

According to Question,

9x + 7 / 4x + 7 = 5/3

3 (9x + 7) = 5 (4x + 7)

27x + 21 = 20x + 35

27x - 20x = 35 - 21

7x = 14

x = 2

Hence, present age of A = 18 years

Present age of B = 8 years

Answer 2

Given :-

• The present ages of a&b are in the ratio of 9:4.
• After 7 years there ages are in the ratio of 5:3.

To find :-

Their present age.

Solution :-

✪The present ages of a & b are in the ratio of 9:4.✪

Let the present age of a be 9x years and the present age of b be 4x years.

★ After 7 years,

Age of a = (9x+7) years

Age of b = (4x +7) years

✪After 7 years there ages are in the ratio of 5:3✪

According to the question,

$\sf{(9x+7):(4x+7)=5:3}\\ \implies\frac{9x+7}{4x+7}=\frac{5}{3}\\ \implies\sf{27x+21=20x+35}\\ \implies\sf{27x-20x=35-21}\\ \implies\sf{7x=14}\\ \implies\sf{x=2}$

★Present age of a = 9×2 = 18 years

★Present age of b = 4×2 = 8 years

Therefore, present age of a is 18 years and present age of b is 8 years.