A store owner buys a total of 4,000 items for two different products. for shipping costs, it is $0.10 per item of product a and $0.04 per item of product
b. if the total shipping cost is $352, which system of equations can be used to determine how much of product a and product b the store owner bought?

Respuesta :

Let the amount of product A bought be x and the amount of product B bought be y, then

x + y = 4,000 . . . (1)
0.1x + 0.04y = 352 . . . (2)

(2) x 10 ⇒ x + 0.4y = 3,520 . . . (3)

(1) - (3) ⇒ 0.6y = 480

y = 480 / 0.6 = 800

From (1), x + 800 = 4,000
⇒ x = 4,000 - 800 = 3,200

Therefore, the store owner bought 3,200 of product A and 800 of product B.