instruction:
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.
question:
Question: The distance between two cities A and B is 330 Km. A train starts from A at 8 a.m. and travel towards B at 60 km/hr. Another train starts from B at 9 a.m and travels towards A at 75 Km/hr. At what time do they meet?

 Option A: 10 a.m

 Option B: 10.30 a.m

 Option C: 11 a.m

 Option D: 11.30 a.m

 Option E: None of these
answer:
Option C


question:
Question: Two stations A and B are 20 km apart on a straight line. One train starts from A at 7 a.m. and travels towards B at 20 kmph. Another train starts from B at 8 a.m. and travels towards A at a speed of 25 kmph. At what time will they meet?

 Option A: 9

 Option B: 10

 Option C: 11

 Option D: 12

 Option E: 8
answer:
Option E


question:
Question: The average age of a class of 20 students is 21 years. The average increased by 1 when the teacher's age also included. What is the age of the teacher?

 Option A: 40

 Option B: 41

 Option C: 42

 Option D: 45

 Option E: 43
answer:

Option C