150 pounds of sugar were packed into 45 bags: some of 2lbs and some 5lbs. How many bags of each weight should there be?

Question

we are supposed to use variables to solve this

Answer 1

X = Number of 2lbs bags

Y = Number of 5lbs bags

X +Y = 45 = Total number of Bags

2X + 5 Y = 150 ( lbs 0

Solve these two equations

2X + 2Y = 90

2X +5Y = 150

Subtracting Eq 1 fro Eq 2

2X+5Y -2X -2Y = 150 -90 = 60

3Y = 60

Y = 20

Plug in

2X +2*20 = 90

2X = 90 - 40 =50

X = 25 = Number of 2lbs bags

Y = 20 = Number of 5lbs bags