sandy bought 65 books for $ 1380 from one shop and 55 books for $ 900 from another shop . what is the average price that sandy paid per book ?
average price per book = ( 1380 + 900 ) / ( 65 + 55 ) = 2280 / 120 = $ 19 the answer is d .
divide(add(1380, 900), add(65, 55))