Basic Mathematics and Measurements
8.0 Rounding off
8.0 Rounding off
The result of computation with approximate numbers, which contains more than one uncertain digit, should be rounded off.
Rules regarding rounding off by convention are as follows,
- Rule 1: If the digit to be dropped is less than $5$, then the preceding digit is left unchanged. e.g. $7.32$ is rounded off to $7.3$
- Rule 2: If the to be dropped is more than $5$, then the preceding digit is raised by one. e.g. $6.78$ is rounded off to $6.8$.
- Rule 3: If the digit to be dropped is $5$ followed by non-zero digit then the preceding digit is raised by one. e.g. $16.451$ is rounded off to $16.5$.
- Rule 4: If the digit to be dropped is $5$m then preceding digits are left unchanged if it is even. e.g. $6,25$ rounding off to $6.2$.
- Rule 5: If the digit to be dropped is $5$, then the preceding digit is raised by one if it is odd. e.g. $4,75$ is rounded off to $4.8$.
