john purchased some shirts and trousers for $ 700 . he paid $ 400 less for the shirts than he did for the trousers . if he bought 5 shirts and the cost of a shirt is $ 20 less than that of a trouser , how many trousers did he buy ?
"given that the total purchase of two items cost 700 . so the average purchase of one item will cost 700 / 2 = 350 . its given as total shirt cost 400 $ less . hence total shirt cost = 350 - 50 and total trouser cost = 350 + 50 5 shirts = 150 $ = = > one shirt = 30 $ one trouser = 30 + 20 = 50 $ total trousers = 550 / 50 = 11 . e"
divide(subtract(700, multiply(5, add(20, 20))), add(add(20, 20), 20))