Solved: Rounding Problem in Physics Class Homework

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AI Thread Summary
The discussion revolves around a physics homework problem involving a man's crossing of a river with a given velocity and current. The student calculated the southward displacement using the river's current and time, arriving at 143 meters, which was rounded to 140 meters for submission. However, the online program marked 140 as incorrect, and the student found that entering 150 was accepted as the correct answer. There are concerns about the accuracy of the online submission system and its handling of significant figures, leading to confusion about proper rounding practices. The student seeks clarification on the discrepancies encountered with the program's feedback.
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Homework Statement



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.



Homework Equations





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..?
 
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those online submissions can be very buggy or their answers can be incorrectly entered. happened a lot to me. answer looks correct. 140m
 
alright thanks i just wanted to make sure I wasn't messing something up
 
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