Question

suppose that 15 inches of wire costs 45 cents
at the same rate, how many inches of wire can be bought for 36 cents

Answer 1

Answer:

12 inches

Step-by-step explanation:

1. Do a proportion

45/15 =3/1 = 36/x

2. cross multiply

3x=36

x =12

Answer 2

Answer:

12 inches

Step-by-step explanation:

To find how much wire you can get for, write the following equation, comparing as a ratio:

$\frac{15}{45}=\frac{x}{36}$

The ratio can be simplified to 1:3 (the inches to cost). Solve for x:

$\frac{1}{3} =\frac{x}{36}$

Cross multiply:

$3x=36$

Divide both sides by 3:

$\frac{3x}{3}=\frac{36}{3}\\\\x=12$

You can get 12 inches of wire for 36 cents.