You are given a mathematical question described with an open-ended vocabulary. Questions in this task involve real-world situations, describing a mathematical problem. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge. Give only one answer for each question.
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Question: One-half of the water in a pond evaporates each week. There are 2,400 gallons of water in the pond at the end of the third week. In gallons, how much less water is in the pond at the end of seventh week than at the end of the third week?
(A)2,250 (B)1,975 (C)1,800 (D)950 (E)150

Answer: A


Question: If, at a certain clothing store, three pairs of dress socks and four pairs of athletic socks cost a total of \$27 and four pairs of dress socks and three pairs of athletic socks cost a total of \$29, what is the combined cost of one pair of dress socks and one pair of athletic socks?
(A)\$26 (B)\$28 (C)\$16 (D)\$8 (E)\$2

Answer: D


Question: The probability of choosing a black marble from a jar containing only black and red marbles is \(\frac { 1 } { 4 } \). Which of the following could be the number of red marbles?
(A)20 (B)22 (C)24 (D)32 (E)35

Answer:
C