Sig Figs in Physics Problems: Explanation for Two Calculations

[p4cifico]

I need an explanation for these two problems

How many sig figs should be retained in the result of the following calculation?

12.00000 x 0.9893 + 13.00335 x 0.0107

and

(11.13-2.6) x 10^4 / (103.05 + 16.9) x 10 ^-6

 

[cesiumfrog]

3 and 2.

Significant fig's is just a rule of thumb, proper uncertainty analysis is more detailed.

 

[Meir Achuz]

I need an explanation for these two problems

How many sig figs should be retained in the result of the following calculation?

12.00000 x 0.9893 + 13.00335 x 0.0107

and

(11.13-2.6) x 10^4 / (103.05 + 16.9) x 10 ^-6

Pick the number in multiplication or division with the least number of SF.
In your first eq., it is 3.
In your second, you first have to do 11.13-2.6=8.5, with 2 SF.