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: How many odd 4-digit positive integers R that are multiples of 5 can be formed without using the digit 3?

 Option A: 648

 Option B: 729

 Option C: 900

 Option D: 1296

 Option E: 3240

Answer: Option A


Question: Question: How much time does a train 150 metres long running at 54 km/hr take to pass a pole?

 Option A: 7.9s

 Option B: 2.5s

 Option C: 7.5s

 Option D: 7.6s

 Option E: 10s

Answer:
Option E