Final answer:
To calculate the percent markup, divide the difference between the selling price and cost price by the cost price and multiply by 100. The closest answer to the correct percent markup of 11.11% is 10%, option (a).
Step-by-step explanation:
The student is asking to find the percent markup on the shirts that a department store sells. To calculate percent markup, we need to determine how much more the store sells an item for than what it paid for it, expressed as a percentage of the cost price.
The store bought 200 shirts at a cost of $3,600, which gives us a cost price of $18 per shirt ($3,600/200 shirts). The selling price is $20 per shirt. The markup in dollars is $20 - $18 = $2 per shirt. To find the percent markup, divide the markup by the cost price and then multiply by 100 to convert it to a percentage.
Percent markup = ($2 / $18) * 100 = 11.11%, which is not listed in the options provided, possibly indicating a mistake in the calculation or the options given. However, based on the given options, 10% is the closest to 11.11%, so option (a) would be the best answer among the choices listed.