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: For an employee to qualify for early retirement at a certain company, the sum of the employee’s age and years of service must be at least 72, If Sue was K years old when she was hired by the company, what is the minimum age at which she could possibly qualify for early retirement.

 Option A: K+36

 Option B: 2K+36

 Option C: (72+K

 Option D: (72-K

 Option E: 2(72-K

A: Option C
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Q: Question: A and B complete a work in 6 days. A can alone can do it in 10 days. If both can together can do the work in how many days?

 Option A: 7

 Option B: 3.75

 Option C: 2

 Option D: 1

 Option E: 8

A: Option B
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Q: Question: Rahul is 30 years older than his daughter Mary. In 20 years Rahul will be twice as old as Mary. What is Mary current age.

 Option A: 12

 Option B: 14

 Option C: 10

 Option D: 16

 Option E: 18

A:
Option C
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