Answer:
To determine which option costs more, let's calculate the total cost of each option.
For the first option of 17 candy bars that cost 79 cents each, we can multiply the number of candy bars (17) by the cost per candy bar ($0.79):
17 candy bars * $0.79/candy bar = $13.43
So, the total cost for 17 candy bars is $13.43.
For the second option of 21 candy bars that cost 65 cents each, we can multiply the number of candy bars (21) by the cost per candy bar ($0.65):
21 candy bars * $0.65/candy bar = $13.65
So, the total cost for 21 candy bars is $13.65.
Comparing the two options, we can see that 21 candy bars at $0.65 each costs more than 17 candy bars at $0.79 each. The difference in cost is:
$13.65 - $13.43 = $0.22
Therefore, 21 candy bars that cost 65 cents each costs $0.22 more than 17 candy bars that cost 79 cents each.