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As you know, to figure out the "answer" using Significant figures, the rules are different for add/subtract than multiple/divide.
- For Add/subtract, it is about the LEAST number of Decimal places of the number that you add/subtract together.
Ex:
- For multiple/divide, it is the number(s) found in the problem with the "least number of Sig Figs.
Ex:
- Rounding to correct answer (either # of Sig fig or decimal places):
- For multiply/divide: count left to right on number to get one (1) more sig fig digit
or
- For add/subtract: Go to lowest decimal place and go one (1) column to right.
- Then if number is a) 5 or above, add one to column to left or b) less than 5, do nothing to column to left.
Ex:
Try on your own:
1) (3.40m)(40.10m) = ____________________ = ________________
- Type of math: ___________ Looking for: Decimal place or # of sig fig (Circle one)
- Where to round:
- Put horizontal line after final column/digit:
- Look at digit to right and round the digit to the left of the line (show number with horizontal line)
- Give correct number after rounding on second line.
2) 3.2m + 4.050m + 12.m = ______________ = _________________
- Type of math: ___________ Looking for: Decimal place or # of sig fig (Circle one)
- Where to round:
- Put horizontal line after final column/digit:
- Look at digit to right and round the digit to the left of the line (show number with horizontal line)
- Give correct number after rounding on second line.