the difference between the ages of two persons is 10 years . fifteen years ago , the elder one was twice as old as the younger one . the present age of the elder person is ?
"let their ages be x years and ( x + 10 ) years then , ( x + 10 ) - 15 = 2 ( x - 15 ) x - 5 = 2 x - 30 x = 25 present age of the elder person = 25 + 10 = 35 years answer is a"
add(subtract(10, subtract(10, add(const_3, const_2))), multiply(subtract(10, add(const_3, const_2)), const_2))