At the grocery store, a 15-ounce box of raisin bran costs $3.19. A 20-ounce box of raisin bran costs $3.59, and a 25.5-ounce box of raisin bran costs $3.99. What is the unit rate for each box of cereal? Round each answer to the nearest cent.

The answers are:

1. The 15-ounce box has a unit rate of 21 cents per ounce

2. The 20-ounce box has a unit rate of 18 cents per ounce

3. The 25.5-ounce box has a unit rate of 16 cents per ounce

Step-by-step explanation:

First, you have to know the relationship between the cent and the dollar ($) and that is:

100 cents = $ 1

Next, let us convert all the prices in dollars to cents, to make calculations easy:

if 100 cents = $1

∴ $3.19 = 3.19 * 100 = 319 cents

$3.59 = 3.59 * 100 = 359 cents

$ 3.99 = 3.99 * 100 = 399 cents.

Next Let us find the unit cost of each box of sereal by dividing the total ounces by their prices:

1. for the 15-ounce box:

15-ounces = 319 cents

∴ 1 ounce (unit cost) = 319 : 15 = 21.26 = 21 cents (to the nearest cent)

2. for the 20-ounce box:

20-ounces = 359 cents

∴ 1 ounce = 359 : 20 = 17.95 = 18 cents (to the nearest cent)

3. for the 25.5 ounce box:

25.5 ounces = 399 cents

∴ 1 ounce = 399 : 25.5 = 15.65 = 16 cents (to the nearest cent)