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: Car X began traveling at an average speed of 35 miles per hour. After 72 minutes, car Y began traveling at an average speed of 41 miles per hour. When both cars had traveled the same distance, both cars stopped. How many miles did car X travel from the time car Y began traveling until both cars stopped?

 Option A: 140

 Option B: 175

 Option C: 210

 Option D: 245

 Option E: 280

A: Option D
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Q: Question: 8 persons can build a wall 140m long in 42 days. In how many days can 30 persons complete a similar wall 100 m long?

 Option A: 12

 Option B: 10

 Option C: 8

 Option D: 6

 Option E: 5

A: Option C
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Q: Question: In the xy-plane, a line has slope 5 and x-intercept 3. What is the y-intercept of the line?

 Option A: -15

 Option B: -3

 Option C: 0

 Option D: 3

 Option E: 9

A:
Option A
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