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: Marge has 3 pumps for filling her swimming pool. When all 3 pumps work at their maximum rates, the swimming pool is filled in 66 minutes. Pump 1's maximum rate is twice the maximum rate of pump 2 and four times the maximum rate of pump 3. How long would it take Marge to fill the pool if she used only pump 3 at its maximum rate ?

 Option A: 2hrs, 48mins

 Option B: 6hrs, 32mins

 Option C: 7hrs, 12mins

 Option D: 13hrs, 4mins

 Option E: 7hrs, 42mins
[A]: Option E


[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


[Q]: Question: The cost price of 25 books is the same as the selling price of ’X’ books. If the profit is 25%, then the value of X is ?

 Option A: 12.8

 Option B: 18

 Option C: 16

 Option D: 15

 Option E: 14
[A]:
Option A