The result of computation with approximate numbers, which contain more than one uncertain digit should be rounded off.

## Rules For Rounding Off

**1. **If the digit to be dropped is less than 5, then the preceding digit is left changed.

**Example:-** X = 7.82 is rounded off 7.8

**2.** If the digit to be dropped is more than 5, then the preceding digit is raised by one.

**Example:- **X = 6.87 is rounded off 6.9

**3.** If the digit to be dropped is 5 followed by digits other than zero, then the preceding digit is raised by one.

**Example:-** X = 16.351 is rounded off 16.4

**4.** If the digit to be dropped is 5 or 5 followed by zeros, then the preceding digit is left unchanged, if it is even.

**Example:- **X = 3.250 is rounded off 3.2

**5.** If the digit to be dropped is 5 or 5 followed by zeros, then the preceding digits is raised by one, if it is odd.

**Example:-** X = 3.750 is rounded off 3.8

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