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: 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


[Q]: Question: Find the average of all prime numbers between 4 and 15.

 Option A: 30

 Option B: 4

 Option C: 9

 Option D: 8

 Option E: None
[A]: Option C


[Q]: Question: A 25 cm wide path is to be made around a circular garden having a diameter of 4 meters. Approximate area of the path is square meters is?

 Option A: 3.34 sq m

 Option B: 3.97 sq m

 Option C: 1.17 sq m

 Option D: 2.98 sq m

 Option E: 2.67 sq m
[A]:
Option A