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.

[EX 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
[EX A]: Option B

[EX Q]: Question: In a local school district, the high school and middle school each received r dollars toward funding for the student arts program. The high school enrolled 600 students and the middle school enrolled 300 students. Later, the middle school transferred s dollars to the high school so that they would have received the same funding per student. Which of the following is equivalent to s?

 Option A: r/3

 Option B: r/2

 Option C: 2r

 Option D: 3r

 Option E: r/9
[EX A]: Option A

[EX Q]: Question: At a certain college 25% of the students join a band, 25% play a sport and 20% both join the band and play a sport. if a randomly selected student is a member of the band, what is the probablility that the student also plays a sport?

 Option A: 1

 Option B: 2

 Option C: 3

 Option D: 4

 Option E: 5
[EX A]:
Option E