Question

10 year ago a was half of b in the ratio of their present age is 3:4 what will be the total of their age present age is​

Answer 1

Step-by-step explanation:

Let the common multiplier of the given ratios be x.

Therefore,

Present age of a = 3x

Present age of b = 4x

Ten years ago:

Age of a = 3x - 10

Age of b = 4x - 10

According to the given condition:

$Age \: of \: a = \frac{1}{2} \times Age \: of \: b \\ \therefore \: 3x - 10 = \frac{1}{2} \times \: (4x - 10) \\ \therefore \: 2(3x - 10) = (4x - 10) \\ \therefore \: 6x - 20= 4x - 10 \\ \therefore \: 6x - 4x= 20 - 10 \\ \therefore \: 2x= 10 \\ \therefore \:x = \frac{10}{2} \\ \therefore \:x = 5 \\ \implies \: 3x = 3 \times 5 = 15 \\ \: \: \: \: \: \: \: \: \: \: \: \: 4x = 4 \times 5 = 20$

Thus,

Present age of a = 15 years

Present age of b = 20 years

Sum of their present ages = 15 + 20 = 35 years.