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: A contractor undertakes to built a walls in 50 days. He employs 40 peoples for the same. However after 25 days he finds that only 40% of the work is complete. How many more man need to be employed to complete the work in time?

 Option A: 60

 Option B: 30

 Option C: 35

 Option D: 20

 Option E: None of these

Answer: Option A


Question: Question: The ratio of a to b to c is 2 to 3 to 4, and a, b, c are positive integers. If the average (arithmetic mean) of the three numbers is 36, what is the value of a?

 Option A: 21

 Option B: 24

 Option C: 25

 Option D: 27

 Option E: 30

Answer: Option B


Question: Question: If x ≠ 0 and (y^2 − xy)/x=y-x, which of the following expressions is equal to its opposite?

 Option A: x^2

 Option B: x^2 – y^2

 Option C: y^2

 Option D: (y + x

 Option E: (x – y

Answer:
Option E