A father is 25 years older then his son. Ten years ago father’s age was 6 times of his son’s age. What is the present age of son?

If x/2 = (x-1)². Find x.

If a, b, c, d, f, g, h, i, j, correspond to 0,1,2,3,4,5,6,7,8 and 9 respectively. Solve the following

(df + fg)/jf - da = …………

What is the simple interest on Rs.8000 at 8% per annum?

If 5x-3x = 2x²/7 Find x?