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Should it not be 14.29% if you are multiplying by 100 to get percent?

Hi gheewala_jen4u, you're quite right, and thank you for spotting that. The final answer should be multiplied by 100, and since this is an error, for which only 1 significant figure is normally appropriate, we can round that to 10%.

Thanks again,
Mr. Dychko

Why do we round to one sig fig? Would it not be 2 sig figs? So 14%?

Thanks for the question harringtonwarriorfitness. One significant figure in an error is typical, two is also OK I suppose, and I've never seen three. Consider how an error is different from a measurement: an error is something that is estimated. An error is never measured. Since an error isn't measured, there's nothing you can do to improve its precision. Since an error is only estimated, that means it can never be very precise, and one significant figure is the usual rule of thumb for errors (or maybe two).

Hope that helps,
Mr. Dychko

Thank you for the fast response! So would 10% and 14% both correct?

Yes, exactly, !0% and 14% would both be correct. If you're want to be extra careful, consider asking the person marking your work what their preference is. Maybe they want you to demonstrate your understanding of the fact that an error is merely estimated, and they prefer only 1 significant figure? Or, maybe rounding to only 1 sig fig hides the fact that you did the error estimate calculation correctly, in which case 2 sig figs is better... It's a judgment call, but both 1 or 2 sig figs should be accepted.