Simple Tricks for Rounding Numbers to the Nearest Cent

Rounding numbers can be a useful tool when dealing with money, especially when working with prices that include cents. Rounding numbers to the nearest cent can help simplify calculations and make them more manageable. Let’s explore some simple tricks for rounding numbers to the nearest cent. 

The first step in rounding numbers to the nearest cent is to identify the place value of the digit to the right of the cent. This digit is commonly referred to as the “hundredths” place. If the digit in the hundredths place is 5 or greater, we round up to the next cent. If the digit is less than 5, we round down to the current cent. 

For example, let’s consider the number 12.573. The digit in the hundredths place is 3, which is less than 5. Therefore, we round down to the current cent, which is 12.57. 

Trick 1: The Five or Greater Rule 

As mentioned earlier, if the digit in the hundredths place is 5 or greater, we round up to the next cent. This is commonly referred to as the “five or greater” rule. To apply this rule, simply look at the digit in the hundredths place and determine if it is 5 or greater. If it is, add 1 to the cent immediately to the left of the hundredths place and drop all digits to the right of the hundredths place. 

For example, let’s consider the number 15.786. The digit in the hundredths place is 8, which is 5 or greater. Therefore, we add 1 to the cent immediately to the left of the hundredths place, which gives us 15.79. 

Trick 2: The Nine Rule 

Another trick for rounding numbers to the nearest cent is the “nine rule”. This rule is used when the digit in the hundredths place is 9. To apply the nine rule, add 1 to the cent immediately to the left of the hundredths place and drop all digits to the right of the hundredths place. 

For example, let’s consider the number 7.899. The digit in the hundredths place is 9. Therefore, we add 1 to the cent immediately to the left of the hundredths place, which gives us 7.90. 

Trick 3: The Round Up or Down Rule 

If you find the five or greater rule and the nine rule too complicated, you can always use the round up or down rule. This rule simply requires you to round up if the digit in the hundredths place is 5 or greater and round down if it is less than 5. 

For example, let’s consider the number 6.504. The digit in the hundredths place is 0, which is less than 5. Therefore, we round down to the current cent, which gives us 6.50. 

Trick 4: The Multiplication Rule 

Finally, another useful trick for rounding numbers to the nearest cent is the multiplication rule. This rule involves multiplying the original number by 100, rounding the result to the nearest whole number, and then dividing the result by 100. 

For example, let’s consider the number 9.162. We first multiply this number by 100, which gives us 916.2. We then round 916.2 to 916 and divide this result by 100, which gives us 9.16. 

In conclusion, rounding numbers to the nearest cent can be a useful tool when dealing with prices and money. The key to successful rounding is to identify the digit in the hundredths place and use one of the above tricks to round up or down accordingly. With a little practice, these tricks can become second