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.
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Question: Question: P is three times as fast as Q and working together, they can complete a work in 12 days. In how many days can Q alone complete the work?

Option A: 11 days

Option B: 16 days

Option C: 13 days

Option D: 15 days

Option E: 19 days

Answer: Option B

Question: Question: If k and w are the dimensions of a rectangle that has area 21, and if k and w are integers such that k > w, what is the total number of possible values of k?

Option A: Two

Option B: Three

Option C: Four

Option D: Five

Option E: Six

Answer: Option A

Question: Question: A 80 gallon solution of salt and water is 10% salt. How many gallons of water must be added to the solution in order to decrease the salt to 8% of the volume?

Option A: 20

Option B: 12

Option C: 13

Option D: 14

Option E: 16

Answer:
Option A