December 23, 2011

PRIME NUMBERS

Prime numbers have captured the hearts of many mathematicians for centuries.  During 18th century, mathematician Christian Goldbach (1690-1764) wrote to Leonhard Euler that he believed it could be shown that every even integer greater than 2 is the sum of 2 primes.  For example, 30 = 23+7 and  36 = 13+23.  Until now, this conjecture has neither been proved or disproved.

Monday, December 19, 2011 - Cool Brain Teaser

Click on the link below and scroll down to the "Freaky Frogs" brain teaser.

http://www.puzzle.dse.nl/teasers/index_us.html#square_puzzle

Can you get the frogs to switch places on the lily pads???

Thursday, December 15, 2011 - Digital Exit Pass

Post your answer. (Make sure to include your first name with your answer.)

5 x 1/2            3 1/3  x  1 5/6

Thursday, December 8, 2011

Instructions

Each student has been assigned a topic from "Skills You'll Need" on page 116 to 119 in Unit #4.  Your task is to review your section and answer the following questions on the construction paper provided.  You will then present your work to the class tomorrow.

Questions
1) Explain how you would solve a problem using this skill.
2) Develop a simple question involving this skill.
3) What is the "golden nugget" (key learning) for this skills?

Once you are done, your final mission is to answer this problem in your notebook.  We will review this question after the presentations tomorrow.

A seventh grade class took a poll to find out their favorite ice cream. 1/4 chose chocolate, 1/4 chose vanilla and 1/2 chose strawberry. 2 kids are lactose intolerant and can't eat ice cream. If there are 22 kids in the class, how many kids liked each flavor? Explain


Once you are finished you can practice using fractions on some of the fractions games available here
- click on this link -  http://www.softschools.com/math/fractions/

Tuesday, December 6, 2011 - Trick to Converting Repeating Decimals into Fractions in Simplest Form!

First I will need a random repeating decimal.

"0.57575757575757..."

Thank you. This would be 19 / 33.

"Wow! How did you do that?"

Simply take the number that repeats, in this case 57, and divide it by however many 9's as there are digits in the original number. Since 57 is 2 digits, then I would divide 57 by 99.

57 / 99 simplifies down to 19 / 33.

We can check our answer by dividing 19 by 33, which equals 0.57575757575757575757

Friday, December 2, 2011

Check out this slideshow of examples of "Geometry in the Real World"!!!

http://www.slideshare.net/CanuteIsInBlock2/geometry-in-the-real-world-2701453

Thursday, December 1, 2011 - Cool Math Trick!!!

Directions

1. Think of your age in years.

2. Multiply your age by 2.

3. Add 10

4. Multiply by 5.

5. Add # of siblings you have.

6. Subtract 50

Look at your final answer; the first 2 digits are your age and the last digit is the number of siblings in your family.  Have someone else try it!  Kind of cool!

Monday, November 28, 2011

Name the item in your freezer or drink that you enjoy, but identify incorrectly on a daily basis.

Multiply Up to 20X20 In Your Head

In just FIVE minutes you should learn to quickly multiply up to 20x20 in your head.  With this trick, you will be able to multiply any two numbers from 11 to 19 in your head quickly, without the use of a calculator.

Try this:

• Take 15 x 13 for an example.
• Always place the larger number of the two on top in your mind.
• Then draw the shape of Africa mentally so it covers the 15 and the 3 from the 13 below. Those covered numbers are all you need.
• First add 15 + 3 = 18
• Add a zero behind it (multiply by 10) to get 180.
• Multiply the covered lower 3 x the single digit above it the "5" (3x5= 15)
• Add 180 + 15 = 195.

That is It! Wasn't that easy? Practice it on paper first!

Post a Comment and let us know what you think of this trick!

Review for Test on Friday, November 25

Breakdown of the test;

1) Multiple Choice - Key Terms
2) Classifying Solids
3) Surface Area
4) Volume

Thursday, November 17 - Problem of the Day

Click on the link below to check out the video on - Squaring Numbers Ending in 5 
  (You will need to scroll down to the video window.)

http://www.onlinemathlearning.com/mental-math-squaring-numbers.html

Once you have seen the video - use mental math to find out 75 squared...

Post your comments now!!!

Monday, November 14, 2011

Geometry and Measurement

Instructions

You will use Geometer’s Sketchpad to complete the questions assigned for this section.

Before – you will need linking cubes. (there are some in the classroom)

1) Explore

Work with a partner – create the isometric dot paper on Geometer’s Sketchpad (just like we did in our last class)

2) Complete the Explore on page 84 with your partner. (once completed – print the pictures.)

During

3) Read over the Connect Section together – pay close attention to the diagonal line segments that make the object look 3D.

After

4) Complete page #86/87 - questions 3, 4 and 6.

Use Geometer’s sketchpad to create your drawings. – print your drawings when you are finished.

Problem of the Day - Friday, November 11, 2011

A cross section of a shape is in the form of a triangle. What could the shape be?


Wondering about the definition of a "cross-section"?

Cross Section
a. A section formed by a plane cutting through an object, usually at right angles to an axis.

b. A piece so cut or a graphic representation of such a piece.

Calling all Math Bloggers!

Hi everyone,

This blog is intended to be used to record interesting facts or ideas about math that we find as we continue to study this year.  We will also use this as a teaching and reference tool throughout the year.

You can submit a comment on a post or create a new post, which will be verified by your teachers before it is displayed on the blog.  Please ensure that you put your first name at the end of the post, so that we know who it was written by.

So blog as much as you want and use this to share your math discoveries...  because you never know... you may be the next FIBONACCI!

Ms. Vallve and Mr. Cordeiro