Question

Ten years ago A was half of B in age. If the ratio of their present ages is 3 : 4, what will be the total of their present ages

A) 15 B) 25 C) 35 D) 45

Answer 1

Let A's age 10 years ago = x

Then, B's age 10 years ago = 2x

(x + 10) / (2x+ l0) = 3/4

→ 4(x+10) = 3(2x+10)

→ 4x+40 =6x+30

→ 2x =10

→ x = 5.

So, the total of their present ages =(x + 10 + 2x + 10)

→ (3x + 20) = 35 years.

Answer 2

Answer:

C) 35

Step-by-step explanation:

Given :

A was half of B in age (10 years ago)

The ratio of their present ages is 3 : 4

Find :

The total of their present ages

Solution :

Let's consider present age of A = 3x And present age of B = 4x

Ten years ago,

Age of A = 3x - 10

Age of B = 4x - 10

According to question:

⇒ 2(3x-10) = 4x - 10

⇒ 6x -20 = 4x - 10

⇒ 6x - 4x = - 10 + 20

⇒ 2x = 10

⇒ x = 10 / 2

⇒ x = 5

Present age of A = 3x

⇒ 3(5) = 3 × 5 = 15

Present age of A = 15 years

Present age of B = 4x

⇒ 4(5) = 4 × 5 = 20

Present age of B = 20 years

The total of their present ages:

15 years + 20 years = 35 years