Answer:
option B.
Explanation:
The original price of Casey's favorite pizza was $5.50, but now it costs $6. To find the percentage markup, we can use the formula:
(markup / original price) * 100%
The markup is the difference between the new price and the original price:
$6.00 - $5.50 = $0.50
So the markup is $0.50.
Using the formula above:
(markup / original price) * 100% = ($0.50 / $5.50) * 100% = 9.09%
Therefore, the pizza was marked up by about 9%, which is option B.