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: On a partly cloudy day, Derek decides to walk back from work. When it is sunny, he walks at a speed of s miles/hr (s is an integer) and when it gets cloudy, he increases his speed to (s + 1) miles/hr. If his average speed for the entire distance is 2.8 miles/hr, what fraction Q of the total distance did he cover while the sun was shining on him?

 Option A: 1/4

 Option B: 4/5

 Option C: 1/5

 Option D: 1/6

 Option E: 1/7

A: Option E
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Q: Question: A machine puts c caps on bottles in m minutes. How many seconds will it take to put caps on b bottles?

 Option A: 60bm/c

 Option B: bm/60c

 Option C: bc/60m

 Option D: 60b/cm

 Option E: b/60cm

A: Option A
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Q: Question: In a recent survey at a local deli, it was observed that 3 out of 5 customers bought a bagel and 5 out of 7 customers bought a coffee. Some customers bought both. If 7 customers are selected, what are the chances that at least 1 customer bought a coffee and a bagel?

 Option A: 27/343

 Option B: 3/7

 Option C: 27/125

 Option D: 341/422

 Option E: 9/125

A:
Option D
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