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: Machine P and Machine Q are each used to manufacture 770 sprockets. It takes Machine P 10 hours longer to produce 770 sprockets than Machine Q. Machine Q produces 10% more sprockets per hour than Machine A. How many sprockets per hour does Machine A produce?

 Option A: 3

 Option B: 5

 Option C: 7

 Option D: 9

 Option E: 11
[EX A]: Option C

[EX Q]: Question: In 165 litres of mixtures of milk and water, water is only 28%. The milkman sold 40 litres of this mixture and then he added 30 litres of pure milk and 13 litres of pure water in the remaining mixture. What is the percentage of water in the final mixture?

 Option A: 29.35%

 Option B: 28. 57%

 Option C: 24. 57%

 Option D: 27. 75%

 Option E: 26. 57%
[EX A]: Option B

[EX Q]: Question: At 1:00 pm, there were 10 grams of bacteria. The bacteria increased to x grams at 4:00 pm, and 22.5 grams at 7:00 pm. If the amount of bacteria present increased by the same fraction during each of the 3-hour periods, how many grams of bacteria were present at 4:00 pm?

 Option A: 14.4

 Option B: 14.7

 Option C: 15.0

 Option D: 15.3

 Option E: 15.6
[EX A]:
Option C