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: There r 4 prime numbers in ascending order. The multiplication of first 3 is 385 and that of last 3is 1001. what is the last number is

 Option A: 12

 Option B: 15

 Option C: 16

 Option D: 13

 Option E: 18

A: Option D
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Q: Question: A coin is tossed two times. What is the probability that there is at the least one tail?

 Option A: 3/4

 Option B: 31/37

 Option C: 31/18

 Option D: 31/10

 Option E: 31/19

A: Option A
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Q: Question: 27 men working 8 hours per day dig 30 m deep. How many extra men should be put to dig to a depth of 50 m working 6 hours per day?

 Option A: 33

 Option B: 66

 Option C: 88

 Option D: 100

 Option E: 281

A:
Option A
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