Question

the difference between the ages of two cousins is 10 years. 15 years ago, if the elder. one was twice as old as the younger one, find their present ages

Answer 1

a-b=10
a-15=2(b-15)
a-15=2b-30
a-2b= -15
a-b=10
solve them
-b=-25
b=25
a-b=10
a-25=10
a=10+25
a=35
a=35,b=25 is answer

Answer 2

difference:- 10 years
suchthat:- 10 and 20
after 15 years:- (10+15) and (20+15)
:- 25 and 35
therefore:- their present ages are 25 and 35