📚 Significant Figures Rules
Master the fundamental rules of significant figures with clear examples and practical tips
🔢 Basic Rules
1. Non-zero digits
All non-zero digits are significant.
2. Leading zeros
Leading zeros are NOT significant.
3. Trailing zeros (with decimal point)
Trailing zeros after a decimal point ARE significant.
4. Trailing zeros (no decimal point)
Trailing zeros without a decimal point are ambiguous.
Solution: 7200. = 4 significant figures (decimal point makes it clear)
🔬 Scientific Notation
Exponential form
Only digits in the coefficient count as significant figures.
💡 Tips for Success
Count from left to right
Start counting from the first non-zero digit.
Decimal point matters
The presence of a decimal point affects whether trailing zeros are significant.
Avoid ambiguity
Use scientific notation or decimal points to make trailing zeros clear.
Practice examples
🎯 Quick Reference
❓ Frequently Asked Questions
What are significant figures?
Significant figures are the digits in a number that carry meaning contributing to its precision. They include all non-zero digits, zeros between non-zero digits, and trailing zeros when there's a decimal point.
Why are significant figures important?
Significant figures help maintain precision in scientific calculations and measurements. They indicate the reliability of a measurement and prevent overstating the accuracy of results.
How do I count significant figures in scientific notation?
In scientific notation (like 3.45 × 10²), only count the significant figures in the coefficient (3.45), not the exponent. The exponent only indicates the magnitude.
What's the difference between significant figures and decimal places?
Significant figures count all meaningful digits, while decimal places count only digits after the decimal point. For example, 123.45 has 5 significant figures and 2 decimal places.
How do I round to significant figures?
To round to n significant figures, identify the nth significant digit, look at the next digit, and round up if it's 5 or greater, down if it's less than 5.
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