Sig fig question?

i dont really get the adding and subtracting the sig fig


for instance, 50-3.56


shouldnt it be just 50?


If so(or not), can you give me other examples associating with addition and subtraction?





same thing for multiplication and division


if you are multiplying


25.7*456.74= is the answer 111700?


If so (or not), can you give me other examples associating with multiplicatrion and division?thank tyou ( please explain to me easily, i dont really understand the sig fig)


thank you for your time

Sig fig question?
For addition/subtraction, your answer can only have the number of places to the right of the decimal as the number in the problem with the LEAST number of places past the decimal. Therefore, 50-3.56 would be 46 (zero places to the right of the decimal)





For multiplication/division, your answer can only have the number of significant figures as the number in the problem with the LEAST number of significant figures. So for 25.7*456.74, 25.7 only has 3 significant figures, so your answer can only have 3 significant figures. The answer would have to be 11700





Hope that helps
Reply:It can be very confusing. 50-3.56 will be 46. This is because in adding/subtracting you go by the number with the least amount of places after the decimal, not the least amount of significant digits. In this case, 50 has zero decimal places, so our answer will have zero decimal places.





In multiplying and dividing you use the number with the least amount of sig figs. In your case 25.7 only has the least amount, three, so our answer will only have three. 11700.





In this example the zeroes are only place holders and not sig figs. To eliminate the ambiguity, we use scientific notation. So, to show 11700 as having three sig figs, we show it as 1.17 X 10^4. The same for the 50 in the first example. Its really only one sig fig. The accurate way to show it would be 5X10^1.