Question

the ratio of the present ages is 1:2 and 5 years back the ratio was1:3. What will be the ratio of their ages 5 years later?

Answer 1

Let their present ages be x and 2x
The ratio of their ages five years before is 1/3

their ages 5 yrs before are x -5 and 2x - 5

i.e.,

x-5/2x- 5 = 1/3

cross multiply ,

2x - 5 = 3x - 15

x = 10

2x = 20

their present ages are 10 and 20 respectively.
Their ages 5 years later are 15 and 25 years.

Ratio of ages 5 yrs later = 15/25 = 3/5 = 3:5

Answer 2

let the ratio 5 years back be x:3x

ratio after 5 years will be (x+5) / (3x+5) = 1/2

cross multiplying

2x+10 = 3x+5

x=5

age 5 years back will be 5 and 15

age today will be 10 and 20 and after five years from today will be 15 and 25

so ratio will be 3:5