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 is faster than B. A and B each walk 24 km. The sum of their speeds is 7 km/hr and the sum of times taken by them is 14 hours. Then, A's speed is equal to?

 Option A: 2 km/hr

 Option B: 3 km/hr

 Option C: 4 km/hr

 Option D: 7 km/hr

 Option E: 8 km/hr

A: Option B
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Q: Question: One water pump can fill half of a certain empty tank in 7 hours. Another pump can fill half of the same tank in 7.5 hours. Working together, how long will it take these two pumps to fill the entire tank?

 Option A: 7 7/13

 Option B: 1 5/8

 Option C: 3 1/4

 Option D: 7 7/29

 Option E: 3 1/2

A: Option D
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Q: Question: Seed mixture X is 40 percent ryegrass and 60 percent bluegrass by weight; seed mixture Y is 25 percent ryegrass and 75 percent fescue. If a mixture of X and Y contains 35 percent ryegrass, what percent of the weight of this mixture is X ?

 Option A:  10%

 Option B:  33.33 %

 Option C:  40%

 Option D:  50%

 Option E:  66.66 %

A:
Option E
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