Question

the present average of a man and his twin sons is 30 years.the ratio of the ages of the man and one of his sons is 5:2.present age of the man is

Answer 1

let age of father be 5x
then age of twins will 2x
given : average of their ages =30
=>(5x+2x+2x)/3=30
=>9x=90
=>x=10
therefore father's age=5x=50
and twin brothers' age =2x=20
hope it will help u

Answer 2

total number of persons =3.
let the present age of father be 5x.
present age of his twins=2x
average age=sum of ages / total number of persons

30=(5x+2x+2x)/3
30=9x/3.
9x=90
x=90/9=10

therefore present age of man is 5×10=50years