Answer:
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)