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ROUNDING OFF WHOLE NUMBERS
The table below shows the number 6275893 and the place value of each digit.
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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