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Homework Help: Rounding problems?

  1. Oct 3, 2007 #1
    1. The problem statement, all variables and given/known data

    A man crossing a river has a velocity due east relative to the river at 5m/s and the current of the river is 1.1 m/s relative to earth south. It takes him 130 seconds to cross the river. How far south of his initial starting point will the man be when he reaches his destination.

    2. Relevant equations

    3. The attempt at a solution
    For my physics class we use an online program to enter our homework, to do this I did 130*1.1 and got 143 it says display answer in 2 sig figs so I rounded it to 140 to get 2 sig figs, however this was wrong so I entered 150 as a guess and got it correct...can somebody explain to me how 143 rounds to 150 I don't get it this isn't the first time something like this has happened with this program so I am wondering if I am doing something with sig figs wrong..?
  2. jcsd
  3. Oct 3, 2007 #2
    those online submissions can be very buggy or their answers can be incorrectly entered. happened a lot to me. answer looks correct. 140m
  4. Oct 3, 2007 #3
    alright thanks i just wanted to make sure I wasn't messing something up
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