# A is three times as old as his son. In ten years, the product of their ages will be 800.How old are they now ?

2
Log in to add a comment

Log in to add a comment

Let the Present Age of A's son be x years .

therefore , Present age of A = 3x years

After 10 years,

A's son's age = x+10

and A's age = 3x +10

According to Question ,

( x+10 )*(3x+10)=800

x(3x+10)+10(3x+10 )= 800

3x² + 10x + 30x +100 = 800

3x² + 40x +100 = 800

3x² + 40x + 100 - 800 = 0

3x² + 40x - 700 = 0

By Hit and Trial method ,

x=10 .

Hope this helps You!!

Thank You!!

Cheers !! :)

So the present age of A = 3x years .

Now A.T.Q

1.After 10 years,

A's son's age = x+10

and A's age = 3x +10

2.

( x+10 )(3x+10)=800

3x² + 10x + 30x +100 = 800

3x² + 40x +100 = 800

3x² + 40x - 700 = 0

Solve it with any method you know .

x=10 .

Present age of A's Son = x= 10 years .

Therefore Present age of A = 3x = 3*10 = 30 years