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 survey is conducted on 800 people from a city. It is found that 6 1% of people surveyed speakHindi, 54.5% people speak Bangla and 37.5% of them speak English. 16.5% people can speak only Hindi and Bangla, 14.5% people can speak only Hindi and English and 6% people can speak only Bangla and English. Answer the following questions based on this information.
How many people are there who can speak only Hindi ?

 Option A: 172

 Option B: 174

 Option C: 176

 Option D: 178

 Option E: 179

A: Option C
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Q: Question: If x is to be chosen at random from the set {1, 2, 3} and y is to be chosen at random from the set {5, 6, 7}, what is the probability that xy will be even?

 Option A:  1/6

 Option B:  1/3

 Option C:  1/2

 Option D:  2/3

 Option E:  5/6

A: Option E
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Q: Question: The average marks of a class of 25 students is 40 and that of another class of 30 students is 60. Find the average marks of all the students?

 Option A: 52.6

 Option B: 52.4

 Option C: 52.1

 Option D: 50.9

 Option E: 52.9

A:
Option D
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