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ROUNDING OFF WHOLE NUMBERS:

ROUNDING OFF WHOLE NUMBERS
Code: WHNR001


As we dealt in the topic of numbers that each digit in a number has its place value. Now lets revise a little bit:-

As discussed earlier that each number has digits, here we discuss about place value what is it? The answer is:-

Each digit has its value according to its position in number. Consider the number 6275 starting discovering from right, the right digit has the lowest value but as you go to the left the digit value increase from 1 to 10 to 100 to 1000 to 10000 to 100000 etc. but we don’t pronounce as normal like ten, hundred but they are pronounced as follows:-

1                      -           Ones

10                     -           Tens

100                   -           Hundreds

1000                 -           Thousands

10000                -           Ten Thousands

100000              -          Hundred Thousands

1000000             -           Millions

 

The table below shows the number 6275893 and the place value of each digit.

6

2

7

5

8

9

3

Millions

Hundred Thousands

Ten Thousands

Thousands

Hundreds

Tens

Ones

 

From the above each digit has the place value for example number 5 occupies the thousands, so it can be written as 5 x 1000, 3 occupies ones so it can be written 3 x 1

 

Rounding off.

The process of rounding off is the same of that in decimal but the different in whole number is that we deal with place value instead of decimal place.

Example 1:

Round off 54682 to the nearest Hundreds.

Solution

1. Our number that is needed for approximation is that with place value "hundreds” that is number 6.

2. As we dealt in decimal that we check the right side number after the considerable number if it is greater or less than 5 so that we can add 1 in our consideration.

3.  Here the right side number is 8 and it is greater than 5 so we add 1 in our number 6 and becomes 7.

4.  after completing checking and adding then all the remaining numbers in the right side of our considerable number should become 0.

5.  Lastly our answer now is 54700 (6 became 7 and 8 & 2 became 0)

 

Example 2:

Round off 7412839 to the nearest Hundred thousands.

Solution

1.  Our number that is needed for approximation is that with place value "Hundred thousands” that is number 4.

2.  As we dealt in decimal that we check the right side number after the considerable number if it is greater or less than 5 so that we can add 1 in our consideration.

3.  Here the right side number is 1 and it is less than 5 so we Don’t add anything in our number 4 and leave as it is.

4.  After completing checking and leaving it as it is then all the remaining numbers in the right side of our considerable number should become 0.

5.  Lastly our answer now is 7400000 (4 remained as 4  and 1, 2, 8, 3 and 9 became 0)

Other examples:

64878   to nearest thousands = 65000   (Check reference in example 1 above)

7651256  to nearest thousands = 7651000 (Check reference in example 2 above)

5426279442    to nearest millions = 5426000000     (Check reference in example 2 above)

27185      to nearest tens = 27190     (Check reference in example 1 above)


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Category: Lower Secondary | Added by: Admin (27/Aug/2013) | Author: Yahyou M. Yahya E
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