An object travels 11 m north and then turns around and travels 25 m south. If the total time of travel is 52 s what is the average speed and velocity of the object.

I used the formula I was told

average speed = distance/time

11+25m= 36m

36m/52 s = 0.692 s is the answer I calculated but my textbook says its 36/52 s = 9/13

average velocity = displacement/time


14m/52 s = 0.269 s is the answer I calculated but its still wrong

14m/52 s = 7/26 is the answer

Can someone please tell me what I'm doing wrong

  • $\begingroup$ Learn to do some math without the calculator. Seriously. You'll be better for it. $\endgroup$ – Bill N Mar 21 '15 at 3:52
  • $\begingroup$ I wasn't told to find the answer without a calculator. $\endgroup$ – Moon CrawlerVG Mar 21 '15 at 20:49

The problem is that 9/13 is approximately 0.692. You used decimals, the book used fractions.

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