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.
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Question: Question: If the average (arithmetic mean) of five consecutive negative integers is 8k – 1, what is the difference between the greatest and least of the five integers?

 Option A: 4K

 Option B: 4k^2 -4k

 Option C: 4-4k

 Option D: 4

 Option E: 4k+4

Answer: Option D


Question: Question: If seven machines working at the same rate can do 3/4 of a job in 30 minutes, how many minutes would it take two machines working at the same rate to do 3/5 of the job?

 Option A: 45

 Option B: 60

 Option C: 75

 Option D: 84

 Option E: 100

Answer: Option D


Question: Question: A train 108 m long moving at a speed of 50 km/hr crosses a train 112 m long coming from opposite direction in 6 seconds. The speed of the second train is:

 Option A: 48 km/hr

 Option B: 54 km/hr

 Option C: 66 km/hr

 Option D: 82 km/hr

 Option E: 85 km/hr

Answer:
Option D