Final answer:
The selling price of a shirt after a 200% markup on a cost price of $9 is $27. The process involves calculating 200% of the cost and adding it to the original cost price. The correct answer is c) $27.
Step-by-step explanation:
The question involves calculating the selling price of a shirt after a 200% markup on the original cost price. If a store buys shirts at a cost price of $9 each and marks them up by 200%, the amount added to the cost price to determine the selling price is calculated as follows:
- First, find 200% of the cost price: 200% = 2 * $9 = $18.
- Next, add the markup to the original cost price: $9 (cost price) + $18 (markup) = $27.
Therefore, the selling price of the shirt would be $27.
The correct answer to the question is c) $27.