Question

Mathur is 60 years old and krishnan is 80 years old.How many years ago was the ratio of their ages 4:6?

Answer 1

Answer:

20 year's ago

Step-by-step explanation:

Given:-

Mathur age is 60 year's

and

Krishnan age is 80 year's

Find:-

how many year's ago their ages was

4 : 6 ratio

let 'r' be the number of year's ago

then,

[ 60 - r ] : [ 80 - r ] = 4 : 6

[ 60 - r ] / [ 80 - r ] = 4 / 6

Cross multiply above we get

6 ( 60 - r ) = 4 ( 80 - r )

360 - 6r = 320 - 4r

-6r + 4r = 320 - 360

-2r = -40

both sides (-) cancel

2r = 40

r = 40/2

r = 20

therefore 20 year's ago their ages in

the ratio of 4 : 6