if 30 % of a number exceeds 20 % of it by 18 , then find the number ?
"let the number be x . 30 % of x = 30 / 100 * x = 3 x / 10 20 % of x = 20 / 100 * x = x / 5 = 2 x / 10 . given that 3 x / 10 - 2 x / 10 = 18 = > x = 180 . required number is 180 . answer : c"
add(divide(18, divide(subtract(30, 20), const_100)), 20)