Divisibility Rules

Hello, hello, hello!

Today we learned the divisibility rules!  Tonight's homework is to complete the divisibility worksheet.  Can't find your homework or were absent?  Click here to get a printable copy of the worksheet.

First we defined the words Factor, Multiple and Product:

This picture may may the concept clearer:

Check out the rules:

For tonight's homework, you will determine which numbers are factors of various values.  Here's an example of how you complete the homework:  (ps- These are the first four problems...  Feel free to copy them if it helps you learn!)

Now, we only went over a few divisibility rules.  There are many others...

2	If the last digit is even, the number is divisible by 2.
3	If the sum of the digits is divisible by 3, the number is also.
4	If the last two digits form a number divisible by 4, the number is also.
5	If the last digit is a 5 or a 0, the number is divisible by 5.
6	If the number is divisible by both 3 and 2, it is also divisible by 6.
7	Take the last digit, double it, and subtract it from the rest of the number; if the answer is divisible by 7 (including 0), then the number is also.
8	If the last three digits form a number divisible by 8, then so is the whole number.
9	If the sum of the digits is divisible by 9, the number is also.
10	If the number ends in 0, it is divisible by 10.
11	Alternately add and subtract the digits from left to right. (You can think of the first digit as being 'added' to zero.) If the result (including 0) is divisible by 11, the number is also. Example: to see whether 365167484 is divisible by 11, start by subtracting: [0+]3-6+5-1+6-7+4-8+4 = 0; therefore 365167484 is divisible by 11.
12	If the number is divisible by both 3 and 4, it is also divisible by 12.
13	Delete the last digit from the number, then subtract 9 times the deleted digit from the remaining number. If what is left is divisible by 13, then so is the original number.

And in a cute poem form...

I hope that this helps!  If you forgot to bring in your Hot Pink sheet or didn't get it completed, please bring it in signed tomorrow!  Thanks!!!!

-Miss K  :)

Wishing for visitors!!!!

Hey there everyone!

I had hoped that I would have had some visitors over Thanksgiving break, but I didn't get any comments! One person did tell me that he made it to my blog, but didn't leave a comment. That got me thinking that maybe you weren't sure how to leave a comment...

What you need to do is go to the bottom of this post (similar to a journal entry) and click on the link that says, "X Comments." (I used the variable X to represent the number because I don't know what number it will be when you see this posting.  A variable is a letter used in math to represent an unknown value.)  Once you click on that link a comment box will appear.  You can then write a short response to me.  When you sign it, feel free to use your first name and last initial.

A few rules:

• Keep it clean: Just because this isn't the classroom doesn't mean that anything goes.  You know what is appropriate and what isn't.
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I might add more rules and suggestions in the future, but I think that this is a good start for now.  Be sure to check in regularly as I plan on posting often.  I will also have survey questions and other items for which I want some feedback, so come to this site prepared to share your thoughts.

Good luck on your proportion homework tonight!  Need some extra help or a reminder of what we talked about?  Click this link for some notes:  Proportions

Have a good night everyone!

-Miss K