praveen age after 10 years will be 3 times his age 3 years back . what is the present age of chris ?
chris present age = x after 10 years = x + 10 3 years back = x - 3 x + 10 = 3 ( x - 3 ) x = 20 answer is a
divide(add(10, multiply(3, 10)), subtract(3, const_1))