Key learning points

1. All numbers can be rounded to a given number of significant figures.
2. Estimating gives you an idea of the size of an answer in context.
3. To estimate an answer you will often round to one significant figure.
4. Sometimes it makes sense to round to a different degree of accuracy when making an estimate.

Common misconception

Keywords

• Estimate - A quick estimate for a calculation is obtained from using approximate values, often rounded to 1 significant figure.

• Significant figures - Significant figures are the digits in a number that contribute to the accuracy of the number.