Final answer:
After 20 minutes of calls, the credit left on Maria's prepaid phone card is a) $44.75, calculated by the function C(x) = 45.75 - 0.05x.Stanley will sell each shirt for $7.50 after a 50% markup on the purchase price of $5 per shirt.
Step-by-step explanation:
The question is about calculating the selling price of a shirt after a 50% markup. Stanley purchased 100 shirts for $500, which means each shirt was bought at $500 / 100 = $5. To calculate the selling price with a markup, multiply the original price by 1 plus the markup percentage in decimal form. Therefore, the selling price will be $5 * (1 + 0.50) = $5 * 1.50 = $7.50 per shirt.The credit left on the card after Maria uses it for 20 minutes of calls can be calculated using the function C(x) = 45.75 - 0.05x. Substituting 20 for x to represent the 20 minutes of calls gives us C(20) = 45.75 - 0.05×20, which equals 45.75 - 1.00, or $44.75. Therefore, the correct answer is A. $44.75.
To find the credit left on the prepaid phone card, we need to evaluate the function C(x) = 45.75 - 0.05x, where x represents the number of minutes of calls.
Substituting x = 20 into the function, we get:
C(20) = 45.75 - 0.05(20) = 45.75 - 1 = 44.75
Therefore, after using the card for 20 minutes of calls, $44.75 credit will be left on the card. The correct answer is option A.