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: The average age of students in section A of 100 students is 20 years and the average age of students in section B of 150 students is 30 years. Find the average age of students in both sections taken together?

 Option A: 26 years

 Option B: 30years

 Option C: 15years

 Option D: 25years

 Option E: 20years

A: Option A
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Q: Question: The sector of a circle has radius of 42 cm and central angle 135o. Find its perimeter?

 Option A: 91.5 cm

 Option B: 92.2 cm

 Option C: 28.9 cm

 Option D: 29.2 cm

 Option E: 183 cm

A: Option E
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Q: Question: The length of a room is 5.5 m and width is 3.75 m. What is the cost of paying the floor by slabs at the rate of $400 per sq. metre.

 Option A: $8250

 Option B: $8350

 Option C: $8650

 Option D: $8450

 Option E: $8500

A:
Option A
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