Rounding Numbers

Here in this page we are going to discuss about rounding numbers concept .Sometimes, it is necessary for us to know to round a number. In certain calculations, it is not necessary to keep more number of values after the decimal points.

Rounding a number can be specified as nearest to the integer or to tenths or to hundredths .etc. By doing these rounding of numbers will help us to calculate certain values easier and it will also avoid lots of confusion.

The value of pi is denoted as a rational number 22/7.

But we generally take the value to be 3.14, because it has non terminating decimal values. Hence pi = 3.14 is one of the sample of rounding numbers.

Let us see some more examples on this topic sample of rounding numbers

Examples on rounding numbers

Here are the examples on rounding numbers -

Example 1: Round the following number to a nearest integer:

(i) 25.67

(ii) 32.43

(iii) 52.04

Solution :

(i) To round a number to the desired form, we need to check the following.

Here, we need to round to an integer. So, we have to check the first decimal value. If the first decimal value is 5 or more, then we add 1 to the integral value and give the final rounded value of rounding to the nearest integer. If the first decimal is less than 1, then we take the integral value and give that as the final value of rounding to the nearest integer.

Now, in 25.67, the first integer is 6 which greater than 5. So we will round the value as 25 + 1 = 26.

Therefore, 25.67 is now rounded to the nearest integer as 26. That will be the final answer.

(ii) 32.43. Here the first decimal is 4, which is less than 5. So, we will take only the integral value which is 32. Therefore, the final rounded value will be 32.

(iii) 52.04. Here the first decimal is 0, which is less than 5. So, we will take only the integral value which is 52. Therefore, the final rounded value will be 52

Example 2: Round the following number to a nearest tenth:

25.67

Solution:

With the same concept, here we are going to consider the second digit after the decimal to round the answer to give the first digit after the decimal.

In 25.67, the second digit after the decimal is 7. 7 is greater than 5. So we need add 1 to 6.

Therefore, the final value after rounding will be 25.7.

Example 3: Round the following number to a nearest hundredth:

12.3427

Solution:

Here we need to consider the third value after the decimal. The third value is 2, which is less than 5.

Therefore, the final value after rounding will be 12.34.

Practice problems

Here are the problems on rounding numbers

1: Round the following number to a nearest integer:

345.67

[Answer: 346]

2: Round the following number to a nearest tenth:

125.327

[Answer: 125.3]

3: Round the following number to a nearest hundredth:

572.438

[Answer: 572.44]

I hope you would have understand better about the concept of sample of rounding numbers.