Checking your subtraction answers - By tecmath
Transcript
| 00:0-1 | get a welcome to take Math Channel . What we're | |
| 00:01 | gonna be having a look at this video is a | |
| 00:03 | method of checking your subtraction questions just to make sure | |
| 00:06 | you got the right answer . Always good method , | |
| 00:09 | a good thing to do . So first off we | |
| 00:12 | could be doing casting out nines in this , but | |
| 00:13 | this is not the quickest and easiest method of doing | |
| 00:15 | this . I'm gonna show you the quickest and easiest | |
| 00:17 | method right now . So say what we were doing | |
| 00:20 | is we're going 3,447,806 . And from this , I | |
| 00:28 | took away 1,391,712 . So I do this and the | |
| 00:37 | answer I get is as follows . Okay , so | |
| 00:40 | six take two is for 80 takes 71 is 97 | |
| 00:45 | take one is 6 40 for take 39 is fine | |
| 00:50 | . Five and 3 to 2 to three take one | |
| 00:53 | is to Okay , so I want to check to | |
| 00:55 | see that this answer more than anything is correct . | |
| 00:57 | So how do I do that ? Well the easiest | |
| 00:59 | way is just doing the reverse of what I just | |
| 01:01 | did . Okay adding the numbers back onto adding the | |
| 01:06 | answer . We get to the number that we took | |
| 01:08 | away to see what equals the number that we started | |
| 01:11 | with . Okay , so for Plus two is 6 | |
| 01:16 | . Okay nine plus 71 because nine plus 10 is | |
| 01:22 | no but nine plus 71 is 80 so that's correct | |
| 01:27 | . Six plus one is seven , 45 plus nine | |
| 01:32 | is 14 carry that one because the four bits right | |
| 01:35 | ? And then the zero plus one plus three is | |
| 01:37 | 42 and one is three . The answer is correct | |
| 01:42 | . That's the fastest method for checking these out . | |
| 01:46 | Okay So it's a fairly um easy method of doing | |
| 01:50 | this . Okay . Just doing the opposite of what | |
| 01:52 | we've done already anyway . Hopefully that was some help | |
| 01:56 | to you . I'll see you next time . Bye | |
| 00:0-1 | . |
Summarizer
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Checking your subtraction answers is a free educational video by tecmath.
This page not only allows students and teachers view Checking your subtraction answers videos but also find engaging Sample Questions, Apps, Pins, Worksheets, Books related to the following topics.
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