each factor of 150 is inscribed on its own plastic ball , and all of the balls are placed in a jar . if a ball is randomly selected from the jar , what is the probability that the ball is inscribed with a multiple of 15 ?
"the # of factors 150 has is 12 so out of 12 factors only four are multiples of 15 : 15 , 30,75 and 150 , itself ; so , the probability is 4 / 12 = 1 / 3 . answer : c ."
divide(divide(choose(15, const_1), 15), power(const_3, const_2))