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Lesson 1: Visually adding within 100

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• Im using this video to help my nephew with regrouping. he doesn't understand why you have to add the ones column first and refuses to add that way. he tends to add mentally which is great but needs to know how to do it out. Any tips on how to get him to add the ones column first and why its so important?
• explain to him that when you add numbers that you need to add the smallest digit first so that your number isn't to small. try to make it fun so that he looks forward and listens. every time he does it the way he's supposed to give him candy Etc...
• Why is this called regrouping, and does it also apply to multiplication and division, not just addition and subtraction?
• Regrouping because it groups the numbers together again. Like words like reload, redo, the re- prefix means 'again' so regrouping means group again. In a away, it the numbers do group again.
Regrouping doesn't apply to multiplication and division. Division has something like regrouping but I think it's called something different.
• What is the relationship between adding and subtracting?
• They're opposites! Adding increases number, while subtracting makes it smaller. For example; 15 + 10 = 25, 15 gets bigger when you add ten, but if you do 15 - 10 = 5, 15 gets smaller since you subtract ten.
• how do you do that whith your crone book
(1 vote)
• I still don't get it.
(1 vote)
• I am using this for review before I get to math I actually add these in my head without grouping or anything else. Is this going to cause me a problem when I get to more complicated math?