Answer: renu is 10 years old and her mother is 40 years old.
Explanation:
let renu be x years old
then her mother would be 4x years
after 5 years her age would be x+5 years
and her mother would be 3(x+5)
equating the ages
3(x+5)=4x+5
3x+15-5=4x
3x+10=4x
4x-3x=10
x=10 years
renu is 10 years old and her mother is 40 years old. after5 years renu would be 15 years and her mother would be 45 years old