Question

the ratio of present ages of two girl is 3:5 5 years ago the ratio of their ages was 1:2 find the present age

Answer 1

$\frac{3 x - 5}{5x - 5} = \frac{1}{2} \\ 5x - 5 = 2(3x - 5) \\ 5x - 5 = 6x - 10 \\ 5x - 6x = - 10 + 5 \\ - x = - 5 \\ x = 5 \\ present \: ages \\ 3x = 3 \times 5 = 15yrs \\ 5x = 5 \times 5 = 25yrs$

Answer 2

Sorry but this is wrong

Let the ratio of ages be 3x and 5x

5 years ago there age was 1y and 2y

Then convert this in equation

3x-5=1y. ------1equation * 5
5x-5=2y. --------2equation *3

15x-25=5y
15x-15=6y
- + -
-10=-y

10=y

Put the value of y in -----1equation

3x-5=y
3x-5=10
3x=10/5
x=2/3

Present ages =3*2/3=2 and 5*2/3=10/3