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: Three persons invested Rs.9000 in a joint business. The second person invested Rs.1000 more than the first and the third Rs.1000 more than second. After two years, they gained Rs.5400. How much third person will get?

 Option A: Rs.2400

 Option B: Rs.3600

 Option C: Rs.2850

 Option D: Rs.2000

 Option E: Rs.3000

A: Option A
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Q: 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

A: Option D
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Q: Question: Find 10 / 11 =110 / ?

 Option A: 111

 Option B: 1100

 Option C: 121

 Option D: 100

 Option E: None of these

A:
Option C
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