- accuracy and precision is very important
in science!!!!
- CALCULATORS have
the brain of an ANT!
- calculators are not
smart enough
to decide what is
precise and what isn't.
-Scientist have made
rules for rounding
off extra digits;
you MUST follow them!
- SIGNIFICANT DIGITS - (S.D)
- non-zero digits are always significant
- if the zero is a "place keeper" it is generally not significant
- i.e 0.0042 = 2 significant digits
- (non-zeros) - any #'s to the left of the decimal point are significant.
- 1.00, 25.05, 11.9000
- zeros after another number are significant
- 1 - 1 S.D 2.104 - yes
0.000001 - 1 S.D. 2.014 - yes
0.0000100 - 3 S.D 2.140 - yes ... because they are all after decimal point.
- when adding or subtracting round to the least precise #
- 7.4212 - 3.54 = 3.8812 > 3.88
- when you multiply or divide round to the # w/ the fewest S.D.'s
- 2.5 x 5.55 = 13.875 > 14
-SCIENTIFIC NOTATION-
- used if we need to write the number 1000 with only 2 S.D's
- 1.0 x 10^3
- shows really big or really small #'s easily
- makes use of power of 10
- i.e. (left) 20^5 = 200 000
(right) 20^-5 = 0.00002
- CALCULATORS - use EE or EXP
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