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: The time taken by a man to row his boat upstream is twice the time taken by him to row the same distance downstream. If the speed of the boat in still water is 42 kmph, find the speed of the stream?

 Option A: 12

 Option B: 15

 Option C: 14

 Option D: 18

 Option E: 19

Answer: Option C


Question: Question: A and B together can do a work in 3 days. If A alone can do it in 12 days. In how many days can B alone do it?

 Option A: 4

 Option B: 6

 Option C: 8

 Option D: 10

 Option E: 25

Answer: Option A


Question: Question: Evaluate: 983 x 207 - 983 x 107

 Option A: 98300

 Option B: 98500

 Option C: 98600

 Option D: 98900

 Option E: 98100

Answer:
Option A