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: A can run 2 km distance in 2 min 20 seconds, while B can run this distance in 3 min 5 sec. . By how much distance can A beat B?

 Option A: 900 m

 Option B: 500 m

 Option C: 120 m

 Option D: 180 m

 Option E: 190 m

A: Option B
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Q: Question: In a school 50% of the students are younger than 10, 1/20 are 10 years old and 1/10 are older than 10 but younger than 12, the remaining 70 students are 12 years or older. How many students are 10 years old?

 Option A: 5

 Option B: 6

 Option C: 7

 Option D: 8

 Option E: 10

A: Option E
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Q: Question: A die is thrown three times. Events X and Y are defined as below:
X : 4 on the third throw
Y : 6 on the first and 5 on the second throw
What is the probability of X given that Y has already occurred.

 Option A: 1/6

 Option B: 1/7

 Option C: 1/8

 Option D: 1/11

 Option E: 1/13

A:
Option A
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