Final answer:
The correct answer is option b. To find the better buy, calculate the price per CD for each pack and compare the results. The 50-pack, at $0.26 per CD, is the better buy than the 30-pack, which comes to $0.3167 per CD.
Step-by-step explanation:
To determine which is the better buy between a 30-pack of blank CDs costing $9.50 and a 50-pack costing $13, you must calculate the price per CD for each pack. The price per CD is found by dividing the total cost of the pack by the number of CDs in the pack.
For the 30-pack: $9.50 ÷ 30 CDs = $0.3167 per CD (rounded to four decimal places)
For the 50-pack: $13 ÷ 50 CDs = $0.26 per CD
Comparing the two prices per CD, you can see that the 50-pack offers a lower cost per CD than the 30-pack. Therefore, option b) the 50-pack is the better buy.
As an illustrative example similar to the question posed, consider the following: In 2001, 10 apples were purchased at 50 cents each, totaling $5.00. This breaks down to $0.50 per apple. Similarly, if 12 bananas cost $2.40, the price per banana is 20 cents. This kind of unit cost calculation helps determine the best value for any purchase.