3rd Grade Math Help!
- Thread starter Judy1993
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ForeverDarkrai
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- Oct 16, 2013
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Have you looked at trying the column subtraction method?
Hi there,
A method that may be good to use is one called the Column Subtraction Method.
For this, you do as it says on the tin: put your subtraction question into a column.
So, for this example, re-write 506-288 as:
506
288 -
___
From here, you start from the units, and work left.
So, you try to do 6-8: which you cannot do without going into negative numbers, so we try to borrow from the tens. Unfortunately, there are no tens to borrow from, so the tens need to borrow from the hundreds.
So, borrowing a hundred will change the hundreds column from a 5 to a 4 and, because a hundred is 10 tens, the tens column is now '10'. But now we can borrow one of these for the units, so the tens column becomes a 9 and the units column become 6 + 10 = 16.
Now we can try 16-8 = 8, so we can write that between the lines in the units column.
Now we look at the tens column - where we have 9-8 = 1, which we can write in the tens column between the lines.
Finally, we look at the hundreds, where we now have 4-2 = 2, which we then write in the hundreds column between the lines.
And the number in between the lines is your answer: 218
If you have any questions about this, please reply back and I may be able to do a video for you to see me work through it in person
Hi there,
A method that may be good to use is one called the Column Subtraction Method.
For this, you do as it says on the tin: put your subtraction question into a column.
So, for this example, re-write 506-288 as:
506
288 -
___
From here, you start from the units, and work left.
So, you try to do 6-8: which you cannot do without going into negative numbers, so we try to borrow from the tens. Unfortunately, there are no tens to borrow from, so the tens need to borrow from the hundreds.
So, borrowing a hundred will change the hundreds column from a 5 to a 4 and, because a hundred is 10 tens, the tens column is now '10'. But now we can borrow one of these for the units, so the tens column becomes a 9 and the units column become 6 + 10 = 16.
Now we can try 16-8 = 8, so we can write that between the lines in the units column.
Now we look at the tens column - where we have 9-8 = 1, which we can write in the tens column between the lines.
Finally, we look at the hundreds, where we now have 4-2 = 2, which we then write in the hundreds column between the lines.
And the number in between the lines is your answer: 218
If you have any questions about this, please reply back and I may be able to do a video for you to see me work through it in person
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