find the average of all prime numbers between 80 and 100
"prime numbers between 80 and 100 are 83 , 89 , 97 required average = ( 83 + 89 + 97 ) / 3 = 269 / 3 = 89.6 answer is d"
divide(add(add(add(80, const_1), add(add(80, const_1), const_2)), add(subtract(100, 80), subtract(100, const_2))), 80)