Question

18. The ages of A and B are in the ratio of 5:
7. Four years from now the ratio of their ages
will be 3: 4. The present age of B is:
a. 20 Years
b.28 Years
c. 15 Years
d. 21 Years​

Answer 1

Answer:

b.28 Years

Step-by-step explanation:

Let the present ages of A and B be 5x and 7x respectively.

(Since there are in the ratio of 5:7)

Four years from age of A will be = 5x + 4

and B's age will be = 7x + 4.

According to question four years from now, the ratio of their ages will be 3:4.

So the equation becomes :

$\frac{5x + 4}{7x + 4} = \frac{3}{4}$

Cross-multiplication gives:

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

or 20x + 16 = 21x + 12

or x = 4

Hence present age of A= 5x = 20 YEARS and

present age of B = 7x = 28YEARS

hope it helps

Answer 2

Answer:

b 28 years is the right answer

Step-by-step explanation:

hope it may help u