Explain in writing what "borrow", "trade" or "regroup" means in subtraction.
Is it that easy or am I missing something?
See
http://mathforum.org/library/drmath/sets/select/dm_borrow.html
It's not hard as it sound.
In subtraction, "borrow," "trade," and "regroup" are terms used to describe the process of carrying over when subtracting numbers. These terms may seem confusing at first, but once you understand the concept, it becomes much easier.
When subtracting two numbers, if the digit in the column being subtracted (the subtrahend) is larger than the corresponding digit in the column being subtracted from (the minuend), we need to borrow or trade.
Let's take an example: 457 - 239.
To subtract these numbers, we start from the rightmost column and work our way to the left.
In the ones column, 7 - 9 results in a negative number. Since we can't have negative numbers in this situation, we must borrow or trade from the tens column.
To do this, we take one unit from the tens column (represented as 5), making it 4, and add it to the ones column making it 17. So now we have 17 - 9, which equals 8.
Moving on to the tens column, we have 4 - 3, which is 1.
Finally, in the hundreds column, we have 4 - 2, which is 2.
Therefore, 457 - 239 equals 218.
To summarize, when we "borrow" or "trade," we take one unit from the higher place value column and add it to the lower place value column in order to perform the subtraction correctly. The term "regroup" is synonymous with "borrow" or "trade" and is commonly used in educational contexts.
Understanding and practicing these concepts will make subtraction easier and help you successfully solve subtraction problems.