More with Factor Trees, LCM and GCF!

We were really busy in class today, but we accomplished a lot!!!

We reviewed last night's homework, tried a challenge problem, worked on GCF and LCM word problems and some of us even got to play a LCM game online!

Take a look at the problems and work from class below and then try the snowball game yourself!

Snowball game:

Tonight's homework is to complete both sides of the prime, composite and factorization worksheet.  Numbers 1-9 should just be identifying if the number is prime (only factors are one and itself) or composite (more factors than just one and itself.)  Numbers 10-19 are factor trees just like the examples above and number 20 is like a factor tree in reverse.  I gave you the factorization, use those numbers to figure out what the original number was!

Tomorrow we will spend a bit of time working on factorization, LCM and GCF, but then we will begin multiplying and dividing fractions!  (It sounds scarier than it actually is!)

-Miss K  :)

Starting to Review for our Quiz on Thursday

Today we began to review for our quiz on Thursday.

After correcting last night's probability homework, we used the people in our class to determine probability:

Then we had a competition to see who could determine the probability of picking certain items from our junk boxes.  You needed to simplify the fractions in order to get the answers correct!  Congratulations to the winners!

We practiced using our divisibility rules in a Venn diagram and circling which numbers worked:

We sorted prime and composite numbers:

We didn't review percentages in class today, but that will also be on the quiz.  You will spend some more time practicing that on Tuesday!

I will not be in school on Tuesday because I will be celebrating the Second day of Rosh Hashanah.  If you are celebrating too, I wish you a sweet New Year.  The substitute on Tuesday will have review sheets to help you prepare for the quiz, and you can work on the study guide as well.

The Study Guide is due on Wednesday.  The quiz is on Thursday.

-Miss K  :)

Divisibility and Prime and Composite numbers

We spent a little time working on more divisibility rules and I introduced the rules for 6 and 9 for a bit of a challenge/extension.

6:  A number is divisible by 6 if it is divisible by both 2 and 3.

9:  A number is divisible by 9 if the sum of its digits is divisible by 9.

After that, we started talking about Prime and Composite numbers.

Some notes from class about prime and composite numbers:

Eratosthenes' sieve  <- Click this link to complete the Sieve of Eratosthenes!

And, the song...  That song......

Homework is to Enjoy your weekend!  See you on Monday!!!!

As a quick reminder, if you forgot to bring in your field trip paperwork, make sure it comes in on Monday!!!

-Miss K  :)

GCF

Greatest Common Factor.  Today we learned about determining the GCF by listing factors and using prime factorization.  Here are some of the notes from class today.

There is more than one way to get the prime factorization of a number, but the answer will always be the same.

Here's the solution of the first problem on tonight's homework:

By finding the prime factorizations of each number, we can compare what they have in common and use those common values to determine the GCF.  In this case, each value has two 3's in it's prime factorization so 9 (3X3) is the greatest common factor.

Let's watch Bob's video from class today:  Bob!

Another video on GCF:  (This guy has even better upside down writing skills than me!)

I hope that this helps!

Tonight's homework is to complete the GCF worksheet.  There are six problems on the paper and we already did #1 in class (see picture above).  You will be able to skip EITHER #4 or #6 if you would like.  If you would prefer to do all problems (that's awesome) you can do both #4 and #6 in addition to the regular ones.  If you do all six problems and get one wrong, it can still go in the 100's box!  There must be 5 correct problems on your paper to go into the 100 box!

Good luck with the homework!  Have a good night!

It was really nice to see all of you today!  I missed you on Friday!

-Miss K  :)

First Quiz Tomorrow.

Hey everyone!  As you know, we have the first quiz of the year tomorrow!  I want to make sure that you are as successful as you can be, so be sure to study this evening!!!

If you want to do a bit more practice, you can work on the problems we did in class.  They are all below in this post.

Practice prime and composite sorting...
Pick your own numbers.  You can check out my old prime and composite post here!

 Practice your divisibility rules...
Pick your own numbers and use the rules from this post to help you remember!

Practice working with fraction models...

Circle 1/5 of these soccer balls.  Or 3/8, or 1/20.

 Try 5/8 of these cowboy boots, or 1/4, or 5/6.

 Circle 1/3 of the ice cream cones, or 2/7.

Practice Probability...

Make up your own probability problems using the items from my junk drawer.  Combine them to make it more challenging.  Be sure to simplify!

 Practice working with ratio...

Use these items to make up ratio problems.  Again, be sure to simplify your answers.

You have your study guide as well as your old homework papers to practice for the quiz tomorrow.  Come in well rested and prepared to show your best work!

-Miss K  :)

Prime and Composite Numbers and a bit of Divisibility Rules

We reviewed a bit of our divisibility rules today in class.  As an intelligent parent mentioned...  Technically all numbers are divisible by all numbers, but they often result in yucky, long decimal values.  When I talk about "divisible" I mean EVENLY divisible.  :)

We completed the large wall Venn Diagram in class today.  A big thanks to my Green class that put ALL of the numbers in the Venn Diagram...

OR THE BOX OF SHAME!



We also began to learn about Prime numbers...

We used the Sieve of Eratosthenes to identify the primes from 1-400.  Try it yourself on this page.

Want some practice learning about Prime and Composite numbers?  Check out this tutorial from Math is fun.

No actual homework this weekend, but we will have a quiz on September 23rd.  I handed out a study guide in class, but it seems like a few people left it behind...  Read below to see what you might have forgotten to bring home!

You are responsible for the following information for this quiz:

1)  Divisibility Rules - you will be given a number and must be able to determine whether it is divisible by 2, 3, 5, or 10 using a Venn Diagram.

          For example:  56,340   

              (You would place the number  in the correct space on the Venn Diagram)

***You must have the divisibility rules memorized***

 

2)  Prime and Composite Numbers - you must know the definitions of prime and composite numbers

          Prime Numbers - the only factors of a prime number are 1 and itself

          Composite Numbers - Composite numbers have other factors besides 1 and itself

You must also be able to sort a list of numbers in two groups: prime & composite

 

3)  Probability & Ratio

You must know how to write a ratio in lowest terms and find the probability of an event as a fraction in lowest terms.

For example ~ Probability:  A junk box contains 5 markers, 6 pom-poms, and 3 beads.  What is the probability of picking a marker from the box without looking?  Answer:  5 out of 14

Ratio:  What is the ratio of pom-poms to markers?  Answer: 6:5 or 6 to 5 or    6

                                                                                                                       5

 

4)  Percent

You must be able to identify the percent when given a fraction or ratio.

=

For example: A junk box contains 10 markers, 6 pom-poms, and 4 beads.  What percent of the pom-poms is in the box?   Answer:  6          30   = 30%

                                                                             20        100

See you all on Monday!  Have a great weekend!

-Miss K  :)