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: A car during its journey travels 30 minutes at a speed of 60 kmph, another 45 minutes at a speed of 80 kmph, and 1 hours at a speed of 70 kmph.The average speed of the car is

 Option A: 63.07 kmph

 Option B: 64 kmph

 Option C: 75 kmph

 Option D: 80 kmph

 Option E: None of these

A: Option D
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Q: Question: A car takes 3hrs less than a truck to cover the distance frm Bombay to pune(192 km). The speed of the truck is 16km/hr slower than car.Find the speed of the car?

 Option A: 40.38

 Option B: 38.38

 Option C: 41.3

 Option D: 48

 Option E: 45

A: Option A
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Q: Question: Which one of the following numbers is the greatest positive integer x such that 3^x is a factor of 729^5?

 Option A: 5

 Option B: 8

 Option C: 10

 Option D: 15

 Option E: 30

A:
Option E
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