find the average of all prime numbers between 60 and 90
"prime numbers between 60 and 90 are 67 , 71 , 73 , 79 , 83 , 89 required average = ( 67 + 71 + 73 + 79 + 83 + 89 ) / 6 = 462 / 6 = 77 answer is e"
divide(add(add(add(60, const_1), add(add(60, const_1), const_2)), add(subtract(90, 60), subtract(90, const_2))), 60)