Question

A 50 lb bag of flour costs $27. How much does 8 lbs of flour cost? Use a proportion to solve.

Answer 1

$4.32

Explanation:

Make a proportion using this setup:

pounds/cost=pounds/cost

A 50 pound bag costs $27, and a 8 pound bag costs $x

50 lb/$27=8 lb/$x

50/27=8/x

Cross multiply

50*x=27*8

50x=216

We want to find what a 8 pound bag, will cost (x). To do this, we need to get x by itself.

Since x and 50 are being multiplied, divide both sides by 50

50x/50=216/50

x=216/50

x=4.32

A 8 pound bag of flour will cost $4.32

Answer 2

$4.32

Explanation:

We want to write a proportion to solve

50 lbs 8 lbs

----------- = --------- -----

27 dollars x dollars

Using cross products

50x = 8*27

50x=216

Divide each side by 50

50x/50 = 216/50

x=4.32