Rounding Numbers

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What is Rounding?

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Rounding simply refers to making a number simpler while keeping its value nearest to what it was. The outcome however will be less exact, but much easier to use. Example: 92 rounded to the nearest ten are 90 since 92 is closer to 90 than to 100. When rounding a number, you first need to see: what are you rounding it to? We can round the numbers to the nearest ten, the nearest hundred, the nearest thousand, and so on.


Rounding Decimals

Let us see how we perform rounding decimals.

Say we want to round the number 728.363. Typically based upon which place value we'll round to, the final outcome will differ. Rounding 728.363:

Rounding to the nearest hundred, we get 700.

Rounding to the nearest ten, we get 730.

Rounding to the nearest one, we get 728.

Rounding to the nearest tenth, we get 728.4.


Tips For Rounding Decimals

In order to avoid confusion or make errors while solving rounding numbers or rounding long decimals, just consider only the number in the place you are rounding to and also the number that follows it. For example, to round 4.273891401 to the nearest hundredth (100th), just look at the number from the left in the hundredths place—7—and the number that follows it—2. Then you can easily round it to 4.27.


How to do Rounding of Fractions?

Rounding fractions works just in a similar manner as rounding whole numbers. The only difference is that rather than rounding to 10s (tens), (100s) hundreds, thousands (1000s), and so on, we just round to 10th (tenths), 100th (hundredths), 1000th (thousandths), and so on. Let’s consider some examples to get a knowhow of the concept better:

6.7199 rounded to the nearest tenth (10th) is 6.7.

2.0731 rounded to the nearest hundredth (100th) is 2.07.

4.8693 rounded to the nearest thousandth (1000th) is 4.869.


How to do Rounding and Sums?

Rounding can certainly make sums easy. For instance, at a merchant shop you might choose articles with the following prices:

Rs. 3.35

Rs. 0.77

Rs. 1.68

If you wanted to know about how much they would cost, you could add up the prices using a calculator, or try to just add them in your head. Or you could simply estimate by rounding off to the nearest rupees, like this:

Rs. 3.00

Rs. 1.00

Rs. 2.00

By rounding off, we could easily find out that we would require about Rs. 6.00 to pay for the items purchased. If you see, this is quite close to the exact number of Rs. 5.8.


Rounding a Number to The Nearest Ten

Round to the Nearest Ten: 799.

Determine the tens digit: the 1st 9 in 799.

Determine the next smallest place value: the 2nd 9 in 799.

Is that digit ≥ five? Thus, round up.

The tens digit increases by one. Because 9+1=10, you would require to carry the 1 and add it to the digit in the 100s place. Each digit then after becomes a zero.

799 rounded to the nearest ten is 800.


Rounding a Number to The Nearest Hundred

Let’s take a digit 4350.

Round to the Nearest Hundred: 4350

Determine the hundreds digit: the 3 in 4350

Determine the next smallest place value: the 5 in 4350

Is that digit ≥ five? : Yes, therefore round up.

Increase the hundreds digit by one, so 3 becomes 4. Every digit after becomes a zero.

4350 rounded to the nearest hundred is 4450.


Did You Know

  • A few statisticians prefer to round 5 to the nearest even number.

  • As a result of rounding 5 to the nearest even number, about half of the time five (5) will be rounded up, and about half of the time, it will be rounded down.

  • In this way, 38.5 rounded to the nearest even number would be 38—it would be rounded down. And, 38.5 rounded to the nearest even number would be 39—it would be rounded up.

Conclusion: In order to learn how to round a number to its nearest multiple, you can check the online round to nearest multiple calculators. The calculator is a useful tool to round to multiples of whole numbers or decimals.

FAQ (Frequently Asked Questions)

Q1. What is Meant by a Round Number?

Answer: A round number is mathematically described as an integer which is the product of a reasonable number of relatively small factors in comparison to its neighbouring numbers, such as 56 = 2 × 2 × 2 × 7. A round number is informally regarded as an integer that ends with one or more "0"s in a provided base. That being said, a rounded number has approximately the same value as the number you begin with, but it is less accurate.

Q2. What is an Example of a Round Number?

Answer: Take for example a number 431. In this case, 431 rounded to the nearest hundred are 400. Since 431 is closer in value to 400 than to 500. When rounding off to the nearest dollar, $2.78 becomes $3.00, because $2.78 is closer to $3.00 than to $2.00.

Q3. How to Round Numbers?

Answer: Below is standard rules for rounding a number:

  • If the number you want to round is followed by 5, 6, 7, 8, or 9, round up the number like 47 rounded to the nearest ten is 50.

  • If the next smallest place value is ≥ to five (5, 6, 7, 8, or 9), you raise the value of the digit you're rounding to by (+1).

  • Any left out digits before the decimal point becomes zeros, and after one’s are dropped.

  • If the number you want to round is followed by 0, 1, 2, 3, or 4, round down the number like 43 rounded to the nearest ten is 40.