TASK DEFINITION: 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.
PROBLEM: 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

SOLUTION: Option B

PROBLEM: Question: A train running at a speed of 36 kmph crosses an electric pole in 12 seconds. In how much time will it cross a 370 m long platform?

 Option A: 37 min

 Option B: 55 min

 Option C: 47 min

 Option D: 67 min

 Option E: 49 min

SOLUTION: Option E

PROBLEM: Question: A man swims downstream 72 km and upstream 45 km taking 9 hours each time; what is the speed of the current?

 Option A: 1.6

 Option B: 1.5

 Option C: 1.3

 Option D: 1.1

 Option E: 1.2

SOLUTION:
Option B