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 certain sum earns simple interest of Rs. 800 in 2 years at a certain rate of interest. If the same sum earns compound interest of Rs.900in the same period of 2 years, What must be the rate of interest?

 Option A: 25%

 Option B: 10%

 Option C: 15%

 Option D: 20%

 Option E: 30%

Answer: Option A


Question: Question: A car traveled 75% of the way from Town A to Town B at an average speed of 75 mph. The car traveled at an average speed of v mph for the remaining part of the trip. The average speed for the entire trip was 50 mph. What is v in mph?

 Option A: 30

 Option B: 35

 Option C: 25

 Option D: 40

 Option E: 45

Answer: Option C


Question: Question: The number of new words that can be formed by rearranging the letters of the word 'NUMBERS' is

 Option A: 2880

 Option B: 7670

 Option C: 1192

 Option D: 5039

 Option E: 1120

Answer:
Option D