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: A, B and C enter into partnership. A invests some money at the beginning, B invests double the amount after 6 months, and C invests thrice the amount after 8 months. If the annual gain be Rs.18000. A's share is?

 Option A: 6029

 Option B: 6299

 Option C: 6000

 Option D: 6018

 Option E: 60012

Answer: Option C


Question: Question: A train running at the speed of 60 km/hr crosses a pole in 21 seconds. What is the length of the train?

 Option A: 350 m

 Option B: 278 m

 Option C: 876 m

 Option D: 150 m

 Option E: 267 m

Answer: Option A


Question: Question: A person goes to his office at 1/3rd of the speed at which he returns from his office. If the avg speed during the whole trip is 36m/h. what is the speed of the person while he was going to his office?

 Option A: 8km/h

 Option B: 9km/h

 Option C: 10km/h

 Option D: 11km/h

 Option E: 24km/h

Answer:
Option E