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: The average age of 31 students in a group is 16 years. when teacher's age is included to it, the average increases by one.What is the teacher's age in years?

 Option A: 31

 Option B: 36

 Option C: 48

 Option D: 45

 Option E: 57

Answer: Option C


Question: Question: A group of hikers is planning a trip that will take them up a mountain using one route and back down using another route. They plan to travel down the mountain at a rate of one and a half times the rate they will use on the way up, but the time each route will take is the same. If they will go up the mountain at a rate of 8 miles per day and it will take them two days, how many miles long is the route down the mountain?

 Option A: 18

 Option B: 20

 Option C: 22

 Option D: 24

 Option E: 25

Answer: Option D


Question: Question: Ages of two persons differ by 16 years. If 6 year ago, the elder one be 3 times as old the younger one, find their present age

 Option A: 12,28

 Option B: 14,30

 Option C: 16,32

 Option D: 18,34

 Option E: 19,34

Answer:
Option B