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.

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
Option D

Question: If a man crosses a 600 m long street in 5 minutes. What is his speed?

 Option A: 7 km/hr

 Option B: 7.1 km/hr

 Option C: 7.2 km/hr

 Option D: 8 km/hr

 Option E: 8.5 km/hr
Option C

Question: A train 450 m long running at 108 kmph crosses a platform in 25 sec. What is the length of the platform?

 Option A: 271

 Option B: 266

 Option C: 350

 Option D: 277

 Option E: 300

Option E