Tuesday, October 27, 2009

Today's Notes

Why we estimate :

- to get close to the answer.
- is to make the problem easier.
- is to know what to expect from our calculations.


1.36 L of O.J. (Orange Juice) and there's 4 of you.

a) estimate how much you each get.

b) calculate how much you each get.

2.0 divided by 4 would equal 0.5 and that is 1/2 over estimating.
1.0 divided by 4 would equal 0.25 and that is 1/4 under estimating.

1.3 divided by 4 would equal 0.3 (0.36)
1.6 divided by 4 would equal 0.4 (0.46)

or you can use long division :

0.34
41.36
- 0

_____
1.3
- 12

_____
16
- 16
_____
0



So then the answer would be that each person would get 0.34 L of O.J.



Here's another question we had to try :



24.6
373.8
- 6

_____
13
- 12
_____

18


The answer would be 24.6.

Here's a really good website where you can learn more on how to divide decimals:

And here's a video on how to divide decimals:








HOMEWORK :


5.4 divided by 0.6


Use numberline and estimating and long or short division.

Don't forget to do your homework!

Monday, October 26, 2009

Dividing decimals

Dividing Decimals



Division means to divide things into equal groups.

Quotient- answer to a division question.


You have 6$ you want to buy fancy glitter pens to to enter the world scrapbooking Olympics. The pens are 40 cents each How many can you buy?


you can get 15 pens.


Describe a way to estimate the answer.


Round 40 up to 50 and 50 goes into 6 12 times because 50 two times = 1$ and 12 divided by 2 is 6



Where do you put the decimal?


15.4 Divided by 3.6= 4277778


round 15.4 to 15 and 3.6 to 3 or round 15.4 to 16 and 3.6 to 4


15 divided by 3= 5


16 divded by 4= 4


both of these numbers are very close to four so we put the decimal in between the 4 and the 2 so your answer is 4.277778


4.4 divided by 0.42= 1047619


round up the 4.4 to 5 and the 0.42 to 5.0 or round down to 4 and 0.4


both those eqations equal 10 so you put the decimal between the 0 and the 4 to make 10.47


Here is a video that explains how to multiply and divide decimals.

http://www.learnalberta.ca/content/me5l/html/Math5.html




















Tuesday, October 20, 2009

Estimating and Calculating Homework

We were given two questions. They were 46 x 4.5 and 64 x 4.5.
Here is how we did it.
46 x 4.5
We started by rounding the number 4.5 to 5. Then we multiplied or calculated 46 x 5= 230 then we had to put the decimal back in, we moved it one place value over, so now the answer is 23.0.There is the estimation.
The next one was 64 x 4.5.
Here is how we did it.
We rounded 4.5 to 5
then multiplied or calculated it by 64, and got 320, again we had to put the decimal back in so we moved it over one place value, so now the answer is 32.0.


Monday, October 19, 2009

homework

post comment
make sure your number of the day is done for tomorrow he is collecting them

Estimating Decimals with Multiplucation

Susie and her family were on a long drive to California she was squished in the back in between her younger brother and older sister so to pass the time she did sudoku she finished her sudoku books. so she begged her parents to stop at a co-op so she could get another sudoku book. when they stopped she found the sudoku books she figured she needed 5 to get her to California. The sudoku books were 1.69 each (tax included) her younger brother estimated it would be 5 dollars her older sister said it would be 10 dollars what are they thinking and how are they estimating


Susie's younger brother estimated it would cost 5 dollars for the 5 sudoku books he was thinking 1.00x 5=5 he was just thinking about 1.00 not the 69 cents.

Susie's older sister estimated that it would cost 10 dollars for the sudoku books she was thinking 2.00x5=10 instead of doing 1.69 she rounded up to 2.00.

Are either of them right?

Susie has 9.00 in her pocket will that be enough?

Yes because it is only 8.45.


2.2x1.8=3960
were does the decimal go?
2x2=4
4 is closed to 3
3960 so therefore it goes in between 3 and 9 3.960

using the same method before i answered......

1)3.9x5.8= 22620
4x6= 24.
24 is closed to 22 so it will go in between the 22 and 6 22.620

2)2.57x0.45=118220
3x0.5= 1.5 (rounding up) so put the decimal point in between the ones 1.18220
11.82220 would be to far.


The Pronghorn sheep weighs 58 kg.
the Dall's sheep weighs 1.5 more than the Pronghorn.
how much more does the Dall's sheep weigh than the Pronghorn?
60x1= 60 kg
60x2= 120 kg
90 kg
50+8= 58
25+4= 29
=
87 kg


Here is a good math link for estimating decimals with multiplication
http://www.mathgoodies.com/lessons/more_on_decimals/multiply_by_whole.html


here is a video on multiplying decimals

Saturday, October 17, 2009

How to Blog


Link- Highlight a word and press the green link button, then look for a site that you think that would build intrest. Then you copy and paste the URL. After you get a link click on preview and test the link.

Image- Find an image (Google images) then save it to your computer then browse and find the image that you saved ( delete it if you don't want it anyomore). You can change the layout and the size. Then you press upload image then done.

Video- go to Youtube.com and find a video that will build intrest about a math topic. Once you find a video click on it then, go to the grey box and highlight and copy the code that is in the box titled EMBED. Then click edit HTML . On your blog, scroll to the bottom then paste the code. Now click compose and preview.

Font- To change font click the arrow next to the word font, then scroll down and find a font that you like and that others can read.

Color- To change the color, click the T with the muliti colored square and then change the color. Only the important facts and titles should be a diffrent color. Don't use to many colors or else it will be distracting. Also, avoid colors like yellow. It's hard to see.

Size- To change the size click the double T's then choose the size you want. Don't make the size to small or to large.

This is a good site to learn how to estimate and round decimals and whole numbers-

Friday, October 16, 2009

772 first scribe

To change size.


To change color.


To change font.


Create a link to the greatest team of all time.


Check out this image I made.

What do you think about this video?




Mark will be the scribe on how to blog.

Everyone else will have to comment on his work. You must leave something nice and something helpful.

Good luck and have fun!

Thursday, October 15, 2009

Wednesday, October 7, 2009

Just trying this out.

Mr. Isfeld made me do this.