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: Find the average of all the numbers between 11 and 36 which are divisible by 5

 Option A: 15

 Option B: 20

 Option C: 25

 Option D: 30

 Option E: 35

A: Option C
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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: Boy sells a book for Rs. 450 he gets a loss of 10%, find CP of the book?

 Option A: Rs.400

 Option B: Rs.450

 Option C: Rs.500

 Option D: Rs.550

 Option E: Rs.600

A:
Option C
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