Question 11 a fruit company delivers its fruit in two types of boxes: large and small. a delivery of 7 large boxes and 9 small boxes has a total weight of 171 kilograms. a delivery of 5 large boxes and 3 small boxes has a total weight of 99 kilograms. how much does each type of box weigh?

Respuesta :

Let x be the weight of a large box and y be the weight of a small box.

7x + 9y = 171 ----- (1)
5x + 3y = 99 ------- (2)

(2) x 3:
15x + 9y = 297 ----- (2a)

(2a) - (1):
15x - 7x = 297 - 171
8x = 126
x = 15.75 --- sub into (2)
5 (15.75) + 3y = 99
78.75 + 3y = 99
3y = 99 - 78.75
3y = 20.25
y = 6.75

Ans: Small box weighs 6.75kg and big box weighs 15.75kg