Rounding Numbers

Although you've probably been rounding for over half your life, this year we will be learning some new rules.

Just like in previous years - 5> number = round down
                                       - 5< number = round up
E.g.- 9.43 (2 s.f.) = 9.4
      - 5.867 (3 s.f.) = 5.87

Now it's time for some fun!
1)     If the rounding digit is = 5 and there are MORE numbers following it, round up.
            -6.32452 (4 s.f.) = 6.325
            -2.500001 (1 s.f.) = 3
2)     If the rounding digit is = 5 and there are NO more numbers following it, round to make the last digit even.
            -4.5 (1 s.f.) = 4
            -43.498735 (7 s.f.) = 43.39874

Adding and Subtracting
When adding or subtracting, calculate the equation first.  Then round to the least exact number (least decimal places)

          
Multiplying and Dividing
When multiplying or dividing, calculate the equation first. Then round to the least amount of significant figures.

Want some more practise?  Here's a good sight to give you a quick review.
http://www.lon-capa.org/~mmp/applist/sigfig/sig.htm