Suppose that 11 inches of wire costs 33 cents.
at the same rate how many inches of wire can be bought for 15 cents
i inches
x
9
?

5 inches

Step-by-step explanation:

11 inches cost 33 cents

x inches cost 15 cents

Note: we let what we are looking for (inches) be "x"

Now, we can set up two ratios (fractions) and equate them to find the inches we can buy for 15 cents.

The set up:

Now we cross multiply and solve for x:

Thus, we can buy 5 inches for 15 cents.

5x+40

5(x + 8)

7x - 49

7(x - 7)

18x + 9

9(2x + 1)

15x - 10

5(3x - 2)

step-by-step explanation:

for number one all you have to do is factor 5 out of 5x + 40

for number 2 factor 7 out of 7x - 49

for number three factor 9 out of 18x + 9

for number four factor 5 out of 15x - 10