How to Round to the Nearest Whole Number

Numbers are rounded to the nearest whole number to eliminate a fraction or the portion of the number to the right of the decimal point. Properly executed, the rounded whole number will never be more than one half different than the absolute number carried to its fraction or decimal precision. Rounding numbers is useful in mathematical steps where a high level of accuracy is not required.

Instructions

1. Determine the fraction of the number or, if the number is stated in decimal format, the portion of the number to the right of the decimal point.

2. Leave the right-hand digit of the whole number as it is if the fraction is less than a half. Add one to the right-hand digit if the fraction is half or greater. Drop the fraction from any reference to the number in the future.

3. Leave the right-hand digit of the whole number as it is if the numbers to the right of the decimal are less than 0.5. If the number to the right of the decimal are 0.5 or greater, add one to the digit to the left of the decimal. If there are multiple numbers to the right of the decimal, start with the digit that is farthest right and apply the rules of rounding number by number until one digit remains to the right of the decimal. The digits to the right of the decimal point are dropped in any further reference to the number.

Tips & Warnings

• A higher level of accuracy can be reached when rounding off groups of numbers by alternating the rounding of the fraction half or the decimal 0.5. The first time a half is encountered the number can be rounded up while the next half encountered in the group of numbers would be rounded down. This is often done in computer software rather than in manual calculations.

References

• CUNY: Rounding Off Numbers
• Enchanted Learning: Rounding Numbers