find the average of all prime numbers between 50 and 70
"prime numbers between 50 and 70 are 53 , 59 , 61 , 67 required average = ( 53 + 59 + 61 + 67 ) / 4 = 240 / 4 = 60 answer is c"
divide(add(add(add(50, const_1), add(add(50, const_1), const_2)), add(subtract(70, 50), subtract(70, const_2))), 50)