A fruit company

Question

A fruit company delivers its fruit in two types of boxes: large and small. A delivery of 2 large boxes and 5 small boxes has a total weight of 57 kilograms. A delivery of 8 large boxes and 3 small boxes has a total weight of 126 kilograms. How much does each type of box weigh?

Answer 1

OK. I'll say L is the weight of a large box, and S the weight of a small box.

 

2L + 5S =  57

8L + 3S = 126

 

Two equations in two unknowns. And there are a couple of ways to solve then. I choose to multiply the first equation by 4.

 

8L + 20S = 228

8L +  3S  = 126

 

Then subtract the second from the first.

 

17S = 102

 

That comes out as S = 6, the small box weighs 6 kg.

 

Either of the two equations can be used to solve for L. I chose the second.

 

8L + 18 = 126

8L = 108

L = 13.5 kg

 

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