what is the average ( arithmetic mean ) of the numbers 2 , 4 , 6 , 8 , 10 , 12 , 14 and 16 ?
"avg = sum of observations / number of observations avg = ( 2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 ) / 8 = 9 answer is a"
divide(divide(multiply(add(2, 6), add(divide(subtract(6, 2), 2), const_1)), const_2), add(divide(subtract(6, 2), 2), const_1))