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 group of hikers is planning a trip that will take them up a mountain using one route and back down using another route. They plan to travel down the mountain at a rate of one and a half times the rate they will use on the way up, but the time each route will take is the same. If they will go up the mountain at a rate of 8 miles per day and it will take them two days, how many miles long is the route down the mountain?

 Option A: 18

 Option B: 20

 Option C: 22

 Option D: 24

 Option E: 25

A: Option D
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Q: Question: If a college has 15 staff for every 700 students, then what is the number of staff for 1400 students?

 Option A: 30

 Option B: 14

 Option C: 12

 Option D: 17

 Option E: 19

A: Option A
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Q: Question: The 120 students in a group are to be seated in rows so that there is an equal number of students in each row. Each of the following could be the number of rows EXCEPT

 Option A:  4

 Option B:  20

 Option C:  30

 Option D:  40

 Option E:  90

A:
Option E
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