the ratio by weight , measured in pounds , of books to clothes to electronics in a suitcase initially stands at 7 : 5 : 3 . someone removes 5 pounds of clothing from the suitcase , thereby doubling the ratio of books to clothes . how many pounds do the electronics in the suitcase weigh ?
"the weights of the items in the suitcase are 7 k , 5 k , and 3 k . if removing 5 pounds of clothes doubles the ratio of books to clothes , then 5 pounds represents half the weight of the clothes . 2.5 k = 5 pounds and then k = 2 pounds . the electronics weigh 3 ( 2 ) = 6 pounds . the answer is d ."
multiply(3, divide(negate(multiply(add(add(7, 5), 3), 5)), subtract(multiply(add(add(7, 5), 3), const_2), multiply(add(add(7, 5), 3), 5))))