Question

ule Univers.
9. The ages of A and B are in the ratio 3: 5. Four years later, the sum of their
ages is 48. Find their present ages.​

Answer 1

Given :-  

• The ages of A and B are in the ratio 3: 5.  

• Four years later, the sum of their ages will be 48.  

To Find :-  

• Find their present ages.

Solution :-  

~Here, we’re given the ratio of the present ages of  A and B . Firstly we will let the present ages and then we can find their ages 4 years later by that assumption. We’re given sum of ages after 4 years as 48 so we can form a equation and solve it to find their present ages.  

According to the given ratios, Let ::  

• Present age of A = 3x  
• Present age of B = 5x  

After 4 years their age will be ::  

• Age of A = 3x + 4  
• Age of B = 5x + 4  

According to the Question :-  

$\sf \implies 3x + 4 + 5x + 4 = 48\;years$

 

$\sf \implies 8x + 8 = 48$

$\sf \implies 8x = 48-8$

$\sf \implies 8x = 40$

$\sf \implies x = \dfrac{40}{8}$

$\sf \implies x = 5$

$\sf \leadsto 3x = 15\;years$

$\sf \leadsto 5x = 24\;years$

 

Therefore ,  

• Present age of A is 15 years and B is 25 years  

Answer 2

Given :

The ages of A and B are in the ratio 3: 5. Four years later, the sum of their ages is 48.

To find :

Find their present ages

Solution :

Let the present ages of A and B be 3x and 5x

So,

Their Ages after 4 years.

A's age = (3x + 4)

B's age = (5x + 4)

Sum of their Ages

(3x + 4)(5x + 4) = 48

3x + 4x + 4 + 4 = 48

8x + 8 = 48

x = 48 - 8/ 8

x = 40/8 = 5

Their Present ages,

3x = 3 × 5

= 15

4x = 4 × 5

= 20