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Subtracting whole numbersSubtracting whole numbers is the opposite of adding whole numbers. Subtraction is the process by which you take one number away from another to get the difference. The following are subtraction problems. They are fairly easy to do mentally or using your fingers.  After you get the difference, you can check your answer by adding The answer for the first subtraction problem is 4 and because 4 + 4 = 8, you know you got the right answer. Subtraction becomes complicated when you subtract a number from a number bigger or equal to 20 For instance, subtract 8 from 85 takes a little more work if you do not know that 77 + 8 is 85, which means that 85 - 8 is 77 A word of advice before I show you how to do 85 - 8. Subtract 8 from 85 means 85 - 8 and you will put 85 on top when you write the problem in vertical column. My students make this mistake all the time. Do not get used to bad habit! It is not the same as subtracting 85 from 8, which is 8 - 85. Later one, when I introduce algebra, I will explain how to get the answer for 8 - 85. To subtract 8 from 85, do the following: Arrange the number in vertical column and rename tens and ones before subtracting.  Because you cannot remove 8 from 5, you have to borrow one ten from 8 tens in the tens place and add that 10 to 5 to make it 15 ones After you do that, you can remove 8 from 15 to get 7 and 0 from 7 to get 7.( whenever you see a blank spot, it means there is nothing there and 0 is nothing. Therefore use 0 as a placeholder for blank space. You can also write your problem as the following to simplify your life:  Just remember that even though you see 7, what you really have is 7 tens or 70. Be very careful of that! Subtracting whole numbers can be very challenging if you do not understand place value.Review place value if you are still struggling with the topics and then get back here. Let us now try to subtract 756 from 5424. Subtracting whole numbers will now take on a new level.  You cannot remove 6 from 4, so you need to borrow 1 ten from 2 tens and add that to 4 to make it 14. Also, you are left with 1 ten, so you cross out 2 and put 1 on top of 2  You cannot remove 5 tens or 50 from 1 ten or 10. Therefore, you need to borrow 1 hundred from 4 hundreds and add that to 10 to make it 110 We write this as 11 but remember that we have 11 tens or 110  Still, you cannot remove 7 hundreds from 3 hundreds. Therefore, borrow 1 thousand from 5 thousands and add that to 3 hundreds to make it 13 hundreds. After you got to this point, you are ready to subtract. 14 -6 is 8 Instead of saying 110 - 50, you can just say 11 - 5 = 6 or 6 tens and so forth...  Who said subtracting whole numbers should be easy? It is easy once you know how to do it, but if you are using my website to learn it, expect me to challenge. However, you will become a professional. Hello! Are you still there? Then, you are ready for one last problem.  The problem above is more tricky. You have to rewrite 1000 1000 = 900 + 90 + 10 Put 10 in the first column; put 90 in the second column, but write only 9; put 900 in the third column,but write only 9.Then, do subtraction. Use this subtraction calculator below to practice  
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|Reading and writing whole numbers
|Adding whole numbers
|Subtracting whole numbers
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|Dividing whole numbers
|Finding the average
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