Study Notes
Estimation involves simplifying numbers while maintaining their overall meaning. It is less precise but easier to use.
- Rounding — simplifying a number to make it easier to work with. Example: 630 rounds to 600 or 700.
- Decimal Rounding — rounding decimal numbers to a specific degree of accuracy. Example: 152.836 rounds to 153 when rounding to the nearest whole.
- Significant Figures — the first non-zero digit in a number is the first significant figure. Example: The first significant figure of 0.00312 is 3.
Exam Tips
Key Definitions to Remember
- Rounding: Simplifying a number while keeping its meaning.
- Decimal Rounding: Rounding decimals to wholes, tenths, or hundredths.
- Significant Figures: The first non-zero digit in a number.
Common Confusions
- Confusing rounding to the nearest whole with rounding to the nearest tenth.
- Misidentifying the first significant figure in numbers with leading zeros.
Typical Exam Questions
- Round 59.1256 to the nearest whole number? Answer: 59
- What is the first significant figure of 0.00312? Answer: 3
- Round 6.82146 to 2 significant figures? Answer: 6.8
What Examiners Usually Test
- Ability to round numbers to the nearest whole, tenth, or hundredth.
- Understanding of significant figures and their application in rounding.
- Application of rounding in calculations to simplify results.