Final answer:
Comparing the total costs of necklaces at Store A and Store B, Candy would pay $4 more at Store A. The answer choices provided do not match the calculated difference. Therefore, there is possibly an error with the provided answer choices as $4 is not listed.
Step-by-step explanation:
The student's question is about comparing the total cost of buying 3 necklaces from different stores with different discount offers. To solve this problem, we need to calculate the total cost in both Store A and Store B and then find the difference.
For Store A: The deal is buying 2 at regular price to get 1 half-off. Two necklaces at the regular price of $10 each will cost $20, and one necklace at half the price will be $5. So the total cost from Store A would be $20 + $5 = $25.
For Store B: The discount is 30% off each necklace. The price after the discount would be $10 - ($10 * 0.30) = $7 per necklace. So the total cost for 3 necklaces from Store B would be $7 * 3 = $21.
To find out how much more it would cost to buy the necklaces from Store A instead of Store B, we subtract the total cost from Store B ($21) from the total cost from Store A ($25). This gives us $25 - $21 = $4 more at Store A.
However, none of the answer choices (A. $9, B. $6, C. $3, D. $7) match the correct calculation of $4. Therefore, it seems like there might be an error in the provided answer choices, as none of them represent the correct difference of $4.