Question

After 12 years I shall be 3 times as old as i was 4 years ago. Find my present age

Answer 1

Let x = present age

 

x + 12  will be my age 12 years from now.

3(x-4)  will be three times as old as I was 4 years ago

 

x+12 = 3(x-4)

Solve for x

 

x+12 = 3x - 12

subtract x from both sides

12 = 2x - 12

add 12 to both sides

24 = 2x

divide both sides by 2

12 = x

 

My present age is 12 years

 

Check:  x+12 = 3(x-4)

          12+12 = 3(12-4)

             24 = 3(8)

             24 = 24

Answer 2

Let the present age be x.
After 12 year from now the age will be (x+12)
3(x-4)will be three times as old as I was 4 year ago.
A/q
$x + 12 = 3(x - 4) \\ x + 12 = 3x - 12 \\ 12 = 2x - 12$
$2x = 24 \\ x = 12$
So,
Present age =12 years