Final answer:
To find the cost of 12 stamps, first calculate the cost of one stamp by dividing the total cost of 15 stamps ($8.25) by the number of stamps (15), which equals $0.55 per stamp. Then multiply the cost per stamp by the number of desired stamps (12): $0.55 * 12 = $6.60.
Step-by-step explanation:
The question asks us to determine how much 12 stamps will cost if 15 stamps are bought for $8.25, and each stamp costs the same amount. First, we find the cost of one stamp by dividing the total cost by the number of stamps.
Total cost of 15 stamps = $8.25
Cost of one stamp = Total cost ÷ Number of stamps
Cost of one stamp = $8.25 ÷ 15
Cost of one stamp = $0.55
Now, to find the cost of 12 stamps, we multiply the cost of one stamp by the number of stamps we want to calculate the cost for:
Cost of 12 stamps = Cost of one stamp × Number of stamps
Cost of 12 stamps = $0.55 × 12
Cost of 12 stamps = $6.60
Therefore, 12 postage stamps will cost $6.60.