Question

A man is 4 times as older as her daughter. After 16 years, he will be twice as old as her daughter. Find the daughters age

Answer 1

let the present age of daughter=x years
let the present age of man=y years
A.T.Q.
y=4x -------_(1)
y+16=2(x+16)
y+16=2x+32
2x-y=16-32
2x-y=-16 ---------(2)
putting the value of y from eq.(1) in eq.(2),
2x-4x=-16
-2x=-16
x=(-16)÷(-2)
x=8
the present age of daughter is 8years

Answer 2

let man age be X and daughter's age be Y
a.t.q
X=4Y (1)
now add 16 to both sides
X+16=2(Y+16)
X+16=2y+32
X-2y=32-16
X-2y=16
X=16+2y
put value in eq1
4Y-2Y=16
2y=16
y=8