hi didnt know wether to put this in phyics or maths but im studying for physics so ill put it here.(adsbygoogle = window.adsbygoogle || []).push({});

Q: What is the percent uncertainty in the volume of a spherical beach ball whos radius is r = 2.86 +or-0.08m?

A: V= 4/3 pie r^3

V = 4/3 pie(2.94)^3 = 106.4463

V = 4/3 pie(2.86)^3 = 97.9911

106.4463-97.9911 = 8.4552

8.4552/97.991 x 100 = 8.6285%

shouldnt 8.6285% be the answer? the book has 9% which i understand could be rounded but considering im doing the scientific notation chapter and it talks about how important it is to be clear with your answer.

i also tried the equation using only 3 significant numbers but i turned out further away from the answer getting something like 8.1%.

have i done something wrong in my calculations??? this question really is simple but i cant think of any other way.

thanks

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# Homework Help: Percent Uncertainty

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