You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: A tank holds x gallons of a saltwater solution that is 20% salt by volume. One Fourth of the water is evaporated, leaving all of the salt. When 5 Gallons of water and 10 gallons of salt are added, the resulting mixture is 33 1/3 % salt by volume. What is the value of x?

Option A: 37.5

Option B: 75

Option C: 100

Option D: 150

Option E: 175

A: Option B
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Q: Question: If the ratio of a to b is 2 to 3 and the ratio of b to c is 1 to 5, what is the ratio of a to c?

Option A: 4/15

Option B: 1/3

Option C: 2/15

Option D: 4/5

Option E: 7/6

A: Option C
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Q: Question: Two taps can separately fill a cistern 10 minutes and 15 minutes respectively and when the waste pipe is open, they can together fill it in 18 minutes. The waste pipe can empty the full cistern in?

Option A: 8 min

Option B: 7 min

Option C: 5 min

Option D: 9 min

Option E: 4 min

A:
Option D
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