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: Rahim bought 4 pillows with the average cost of $5. If Rahim also buys the fifth pillow with the price of $ 10, what is the average (arithmetic mean) price of those 5 pillows?

 Option A: $6

 Option B: $5

 Option C: $5.5

 Option D: $6.5

 Option E: $7

Answer: Option A


Question: Question: The least number of complete years in which a sum of money put out at 20% C.I. will be more than doubled is?

 Option A: 3

 Option B: 4

 Option C: 9

 Option D: 3

 Option E: 5

Answer: Option B


Question: Question: Andrew started saving at the beginning of the year and had saved $240 by the end of the year. He continued to save and by the end of 2 years had saved a total of $600. Which of the following is closest to the percent increase in the amount Andrew saved during the second year compared to the amount he saved during the first year?

 Option A: 11%

 Option B: 25%

 Option C: 44%

 Option D: 50%

 Option E: 125%

Answer:
Option D