Question

2 years ago, Mohan was 3 times as old as his son. After 2 years, twice his age will be equal to five times that of his son. Find their present age

Answer 1

Answer:

let age of mohan be x and his son be y

2x=5y

x=(5y/2)

(x-2)=(y-2)3

(5y/2)-2=3y-6

5y-4=6y-12

6y-5y=12-4

y=8

x=(5y/2)

x=20

Answer 2

Answer:

Let

Present age of Father = f

Present age of Son = s

Two years ago

f-2=s-2

Father was 3 times as old as his son

f-2=3(s-2)

f-2=3s-6

f=3s-6+2

f=3s-4............(1)

and 2 year hence,

f+2=s+2

then twice his age will be equal to 5 times that of his son

2(f+2)=5(s+2)

2f+4=5s+10

2f=5s+10-4

2f=5s+6.............(2)

Put the value of f in (2) from (1)

2(3s-4)=5s+6

6s-8=5s+6

6s-5s=6+8

s=14

Put the value of s in (1)

f=3s-4............(1)

f=3(14)-4

f=42-4

f=38

Present age of Father = f = 38 years old

Present age of Son = s = 14 years old