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.

[EX Q]: Question: John left home and drove at the rate of 45 mph for 2 hours. He stopped for lunch then drove for another 3 hours at the rate of 45 mph to reach his destination. How many miles did John drive?

 Option A: 235 miles.

 Option B: 245 miles.

 Option C: 225 miles.

 Option D: 265 miles.

 Option E: 275 miles.
[EX A]: Option C

[EX Q]: Question: The average salary per head of the entire staff of an office including the officers and clerks is Rs.90. The average salary of officers is Rs.500 and that of the clerks is Rs.84. If the number of officers is 2, find the number of officers in the office?

 Option A: 620

 Option B: 720

 Option C: 820

 Option D: 920

 Option E: 1020
[EX A]: Option C

[EX Q]: Question: Two trains are moving at 45kmph and 70 kmph in opposite directions. Their lengths are 150 m and 100 m respectively. The time they will take to pass each other completely is?

 Option A: 40/6 sec

 Option B: 43/6 sec

 Option C: 47/6 sec

 Option D: 40/3 sec

 Option E: 40/7 sec
[EX A]:
Option C