Do you add first or round first?
Keeping this in view, do you round before or after adding?
As you can see, in finding a round sum, it is quickest to round the numbers before adding them. 1. Some statisticians prefer to round 5 to the nearest even number. As a result, about half of the time 5 will be rounded up, and about half of the time it will be rounded down.
Furthermore, do you round when adding significant figures? When you add or subtract, you assign significant figures in the answer based on the number of decimal places in each original measurement. However, the 35.7 miles measurement extends only to the tenths place. Therefore, you round the answer to the tenths place, from 671.05 to 671.1 miles.
Accordingly, what is the Sigfig rule for addition?
Your answer cannot be MORE precise than the least precise measurement. For addition and subtraction, look at the decimal portion (i.e., to the right of the decimal point) of the numbers ONLY. 1) Count the number of significant figures in the decimal portion of each number in the problem.
How many significant figures does 100 have?
|(1)||1000||1x103 -- so one sig fig|
|(2)||0.001||1x10-3 -- so one sig fig|
|(3)||100.||1.00x102 -- so three sig figs|
|(4)||0.00100||1.00x10-3 -- so three sig figs|
|(5)||100 (with two sig figs)||1.0x102 -- so two sig figs|