Mathematics for IGCSE & O level - Using A Calculator (Section 1 - No. 8)
What should you remember when rounding numbers in the calculation?
Always round down to ensure accuracy.
Round intermediate values to a high number of significant figures.
Round intermediate values to one more significant figure than the final answer.
Only round the final answer.
Uitleg
To avoid compounding rounding errors, round intermediate calculations to one more significant figure than the final answer.