Respuesta :

Answer:

Hello, this is a proportion problem! You need to set up a proportion with length of wire on top and cost on the bottom.

15 = x

90 66

Now, you cross multiply. 15 x 66 and 90 times x.

15(66) = 90x

990 = 90x

Divide both sides by 90.

x = 11inches

Answer:

  • 12 inches

-----------------------------

15 inches of wire costs 90 cents, then 1 inch of wire costs:

  • 90/15 = 6 cents

The length of wire for 72 cents:

  • 72/6 = 12 inches