Final answer:
Jonah saves $0.2261 per ounce by buying raisins in bulk, which is found by comparing the cost per ounce from the grocery store ($0.4167 per ounce) to the bulk order cost per ounce ($0.1906 per ounce).
Step-by-step explanation:
To determine the savings per ounce when Jonah buys raisins in bulk, we need to calculate the cost per ounce for both purchasing options and then compare them.
First, we calculate the cost per ounce at the grocery store:
$3.75 for 9 ounces gives us $3.75 ÷ 9 ounces = $0.4167 per ounce.
Next, we calculate the bulk order cost per ounce:
5 pounds is equivalent to 5 × 16 ounces = 80 ounces.
$15.25 for 80 ounces gives us $15.25 ÷ 80 ounces = $0.1906 per ounce.
Now, we can find the savings per ounce:
Savings per ounce = $0.4167 - $0.1906 = $0.2261
Therefore, Jonah saves $0.2261 per ounce by purchasing raisins in bulk.