Merry joined an online community that charges a monthly fee of $15. A one-time enrollment fee of $50 was charged when she joined. Which of the following represents the total amount of fees that Merry has paid to the community organizers after m months, in dollars?
A. 15m + 50
B. 15 + 50m
C. 15m - 50
D. (15 + 50)m
Answer:A
Merry joined an online community that charges a monthly fee of $15. A one-time enrollment fee of $50 was charged when she joined. Which of the following represents the total amount of fees that Merry has paid to the community organizers after m months, in dollars?
A. 15m + 50 B. 15 + 50m C. 15m - 50 D. (15 + 50)m
Explanation: A Whenever the question includes variables, plug in. If m = 2, then Merry would pay the one-time enrollment fee plus 2 months' worth of monthly fees, which is 50 + 15(2) = 80. Plug in 2 for m in the answer choices to see which answer equals the target number of 80. In (A), 15(2) + 50 = 80. This is the target number, so leave this answer, but be sure to check the other choices just in case. In (B), 15 + 50(2) = 115. In (C), 15(2) - 50 = -20, and in (D), (15 + 50)(2) = 130. Since none of the other answer choices equals the target number, the correct answer is (A).