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: A can complete the job in 4 hours and B can complete the same job in 3 hours. A works for 1 hour and then B joins and both complete the job. What fraction of the job did B complete

Option A: 1/7

Option B: 3/10

Option C: 1/2

Option D: 5/6

Option E: 8/9

Answer: Option A

Question: Question: Find the number of ways of arranging the letters of the word "MATERIAL" such that all the vowels in the word are to come together?

Option A: 1887 ways

Option B: 1440 ways

Option C: 1657 ways

Option D: 1652 ways

Option E: 6745 ways

Answer: Option B

Question: Question: Find the average of first 30 natural numbers.

Option A: A

Option B: B

Option C: C

Option D: D

Option E: E

Answer:
Option D