Question

the ages of ruby and reshma are in the ratio 5:7 . four years later their ages will be in the ratio 3:4

Answer 1

let the common factor be X
ruby's age=5x
reshma s age=7x

four years later the ages of
ruby=5x +4
Reshma=7x+4

therefore,
5x +4
______=3/4

7x+4

20x+16=21x+12
therefore x=4

thus ruby's age=5(4)=20years
Reshma s age=7(4)=28 years

hope this helps!!

Answer 2

Age of ruby=5x
Age of reshma=7x

After 4 years
Age of ruby=5x+4
Age of reshma =7x+4

(5x+4)/7x+ 4=3/4
4 (5x+ 4)=3(7x+ 4)
20x+16 =21x+12
16-12=21x-20x
4=X
x=4

Age of ruby = 3 (4 )=12
Age of reshma = 4 ( 4 ) = 16