the average height of 20 students in a class was calculated as 175 cm . it has later found that the height of one of the students in the class was incorrectly written as 151 cm whereas the actual height was 111 cm . what was the actual average height of the students in the class ?
"the total height was 40 cm too much . the average height should be reduced by 40 cm / 20 = 2 cm the answer is b ."
divide(subtract(multiply(20, 175), subtract(151, 111)), 20)