# Rule Of Rounding Off

While rounding off measurements, we use the following rules by convention

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

**Example:** x = 7.82 is rounded off to 7.8, again x = 3.94 is rounded off to 3.9.

**Rule 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 to 6.9, again x = 12.78 is rounded off to 12.8.

**Rule 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 to 16.4, again x = 6.758 is rounded off to 6.8.

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

**Example:** x = 3.250 becomes 3.2 on rounding off, again x = 12.650 becomes 12.6 on rounding off.

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

**Example:** x = 3.750 is rounded off to 3.8, again x = 16.150 is rounded off to 16.2.