TASK DEFINITION: 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.
PROBLEM: 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

SOLUTION: Option C

PROBLEM: Question: Two pipes A and B can separately fill a cistern in 10 and 15 minutes respectively. A person opens both the pipes together when the cistern should have been was full he finds the waste pipe open. He then closes the waste pipe and in another 4 minutes the cistern was full. In what time can the waste pipe empty the cistern when fill?

Option A: 7

Option B: 9

Option C: 5

Option D: 4

Option E: 8

SOLUTION: Option E

PROBLEM: Question: The inverse ratio of 3: 2: 1 is?

Option A: 2:9:5

Option B: 2:3:0

Option C: 2:3:5

Option D: 2:3:6

Option E: 2:3:1

SOLUTION:
Option D