Skip to main content Print Help Skip to main navigation

Tips for 'Estimation'


• Estimate the answer before you start a calculation. You can then check whether your answer makes sense - is it about the right size? 

• To round to the nearest 10: round down numbers that end in 4 or below; round up numbers that end in 5 or above. 

• To round to the nearest 100: round down numbers that end in 49 or below; round up numbers that end in 50 or above. 

• Rounding to the nearest 10 will give you a more accurate estimation than rounding to the nearest 100. 

• If you round numbers before you do a calculation, the result will be less accurate than if you round the final answer. This can be important when solving problems, but approximate calculations (rounding first) can still help you to check the size of the answer.