Significant Digits
Master significant digits in Grade 10 science and math. Count nonzero digits, zeros between significant figures, and trailing zeros after decimal points to express measurement precision.
Key Concepts
Significant digits indicate the precision of a measurement. Rules for counting them are: 1. Nonzero digits are significant. 2. Zeros between significant digits are significant. 3. Leading zeros are not significant. 4. Zeros after the last nonzero digit and to the right of a decimal point are significant.
The number $405.08$ has 5 significant digits. The number $0.0075$ has 2 significant digits. The number $0.09100$ has 4 significant digits, as the trailing zeros after the decimal are counted.
Significant digits are the 'trustworthy' numbers in a measurement. They tell you how precise that measurement really is. Think of leading zeros as just placeholders, like the empty space before a sentence begins. But those trailing zeros after a decimal? They're super important—they prove you measured carefully right down to that tiny fraction!
Common Questions
What are the rules for counting significant digits?
Nonzero digits are always significant. Zeros between nonzero digits are significant. Leading zeros are never significant. Trailing zeros after a decimal point are significant.
How many significant digits does 0.00450 have?
0.00450 has 3 significant digits: 4, 5, and the trailing zero after the 5. The leading zeros before 4 are not significant since they only indicate the decimal position.
How do significant digits affect calculations?
For multiplication and division, round the result to the fewest significant digits in the problem. For addition and subtraction, round to the fewest decimal places.