A package of 8 frankfurters costs $5.00 and a package of 12 hot dog buns costs $3.00. If Jeffrey makes a hot dog sandwich using only a frankfurter and a bun, what percent of the cost of his hot dog sandwich comes from the bun?

Buns = 28.57%

Explanation:

Giving the following information:

A package of 8 frankfurters costs $5.00 and a package of 12 hot dog buns costs $3.00.

First, we need to calculate the unitary cost of the frankfurters and buns.

Frankfurters = 5/8 = $0.625

Buns = 3/12 = 0.25

Now, the percentage of buns per hotdog:

Total unitary cost = 0.625 + 0.25 = 0.875

Buns = 0.25/0.875 = 0.2857 = 28.57%