Wednesday, May 26, 2010

The Best Measure of Central Tendency


The first thing you should know about getting the best measure tendency is getting the mean, median, mode and range is the priority. But to get that first you need to rearrange the data set.
The set you need to arrange is the shirts because it is the topic. This should be arrange in smallest to biggest, so for this one its 7,7,7,8,9,9,10,11,12,50.

Then after that you should find the main things, mean, median, mode, and range.

Mean is 13
Mode is 7
Median is 9
Range is 43

In this case the median is the best measure of central tendency because its closest to everyone except for the 50.

How many shirts should the man buy for the next 30 weeks?
If 9 is the best representative I should multiply 9 to 30 like this:
9x30=270 shirts should the man buy.











Tuesday, May 25, 2010

Choose the Best Measure of Central Tendency

Here is a chart show how many shirts a man sold in 10 weeks.
Now what I want you to do is find the Mean, Median, Mode, and Range

The first thing I'll do is rearrange the set of data.
7,7,7,8,9,9,10,11,12,50. Mean 13 Median 9 Mode 7 Range 43

The best measure of central tendency, in this case, is the median (9) since many numbers in the set of data are close to it.

How many shirts should the man buy for the next 30 weeks?
Since nine is the best representative, I will multiply 9 by 30.
9x30=270
The man should buy 270 shirts.

Here are some things I found to help you understand measures of central tendency more:
This one I actually made,
Here is a video.

and lastly, I found this website that might also come in handy,

Homework Pg. 449-451 #3-16

Well thank you for reading my blog, hope you enjoyed!

Wednesday, May 19, 2010

Range and Outliers

Range - Positive Difference between the largest and smallest values in a data set.

eg. 6,2,9,4,3 Re-order the data set.
2,3,4,6,9 Subtract smaller value from larger value.
9 - 2 = 7. 7 is your range.
eg. -8,-1,-3,-5 Re-order the data set.
-8,-5,-3,-1 Subtract smaller value from larger value.
(-8) - (-1) = 7

Outlier - A value that is much smaller or larger than the other data values, or the "outcast".
-A data set may have one or more outliers or no outliers at all.

Try to find the Range of the following.

a). 7,4,3,6,2,5,8,3 b).11,8,8,5,7,6,7,6,6 c). -4,3,-1,0,2

Try to find the Outlier of the following.

a). 18,19,79,17,20,12 b). 14,14,16,15,1,16 c). 98,202,99,91,2,95,89,88,94

Watch this video to learn more about Range and Outlier.

http://www.youtube.com/watch?v=GnIP69AnkDQ&feature=related

Thank you for reading my post.

Please leave a comment on anything I did wrong or think I should add next time.



Range -The positive difference between the largest and smallest values in a data set.

Eg. 6, 2, 9, 4, 3 - data set

2, 3, 4, 6, 9 - ordered from least to greatest

9 - 2 = 7

The range is 7

Example: -8, -1, -3, -5

-8, -5, -3, -1

(-1) - (8) = 7

The range is 7

outliers-A value that is much smaller or larger than the other data values
A data set may have one or more outliers or no outliers

* It's like,finding something that doesn't belong

Find the range of the following

a) 7, 4, 3, 6, 2, 5, 8, 3

2, 3, 3, 4, 5, 6, 7, 8

8 - 2 = 6

The range is 6


b) 11, 8, 8, 5, 7, 6, 7, 6, 6

5, 6, 6, 6, 7, 7, 8, 8, 11

11 - 5 = 6

The range is 6


c) -4, 3, -1 , 0, 2

-4, -1, 0, 2, 3

3 - (-4) = 7

The range is 7


Find the outliers of the following

a) 18, 19, 79, 17, 20, 12 - 12, 17, 18, 19, 20, 79 - The range is 79

b) 14, 14, 16, 15, 1, 16 - 1, 14, 14, 15, 16, 16 - The range is 1

c) 98, 202, 99, 91, 2, 95, 89, 88, 94 - 2, 88, 89, 91, 94, 95, 98, 99, 202- The range is 2 and 202


Monday, May 17, 2010

The Mean

What is a Mean?

Mean- is a measurement of central tendency.
- the sum ( answer of addition) of a set of values divided by the number of values in a set or to put in a simple way, add all the numbers given and divide in how many you've add.
- AKA. Getting the average

eg. 4,5,8,99

= 4+5+8+9+9
__________
5
= 35
___
5

= 7

Try This:


A) 7,8,6,9,9,5,7,7,8,4
B) 300,250,400,300,250

The meaning of mean

Mean - a measure of central tendency - sum (adding) of a set of values divided by the numbers of value in the set.
eg.; 4, 5, 8, 9, 9













a.k.a
; average

To refresh your memory:
Mode
means the most frequently occurring number in a set of data.
Median means the middle number in a set of data after the data has be arranger or reordered.

Try these (Find mode, median and mean):

a) 4, 5, 6, 7, 7, 7, 8, 8, 9, 9
b) 250, 250, 300, 300, 400

Compare your answers to these:

a) mode = 7 median = 7 mean = 7

b) mode = 250 & 300 median = 300 mean = 300


Homework: Math Links; Page-431, 433 #1-16


Here are some videos:










PS: KC chiefs & Isfeld are the best :D !
Beat that stand up boy ;)

Friday, May 14, 2010

Homework and extra practice

Your homework for the weekend is pages 426 - 427 numbers 1 - 17 plus the math link.

Try some of these problems for extra practice:

Working With Data1. List all the four-digit numbers that are even, have a 6 in the tens place, and whose digits add to 12. 2. Is 349 ´ 0.9 greater than, less than, or equal to 349? How do you know? ______________________________________________________________ ______________________________________________________________
3. Suppose you know that 48 ÷ 16 = 3. Without finding the exact answer, tell whether the answer to 48 ÷ 15.99 is greater than, less than, or equal to 3. Why? ______________________________________________________________ ______________________________________________________________
4. Use the multiplication below to answer the questions that follow. a) Can E be 2? Explain. ___________________________________________________________ ___________________________________________________________ b) What is the value of D? Why? ___________________________________________________________ ___________________________________________________________ c) What is the value of G? How do you know? ___________________________________________________________ ___________________________________________________________

Tuesday, May 11, 2010

Algebra, T - Chart, and Linear Graph


Algebra, T- Chart, and Linear Graph: Algebra, T- Chart, and Linear Graph

1.) This diagram shows that a cabin with 1 room has 2 doors,

a cabin with 2 rooms has 5 doors, and a cabin with 3 rooms

has 8 doors.


Draw the next 2 cabins.


How many doors will a cabin with 10 rooms have?


~ 29 DOORS

Write an algebraic equation for this pattern.

~ 3x - 1 = y



2.) For this linear relationship y = 2x - 1. Complete

the following table of values.



Create a graph representing these values.



Describe a pattern in real life that the linear relation

y = 2x - 1 could represent. Make sure you explain what

both x and y represent.


eg.

There's a bag of chip that costs $2.00. I bought 2 bags of chip

(let's just say I bought 2 bags). I multiplied it by 2.

Then I remembered I have a coupon worth $1.00 off.

3 = 2(2) -1

HERE ARE SOME VIDEOS TO HELP YOU!

(Sorry guys, I can't put the video directly to this post.

The computer said it's an error page.)

http://www.youtube.com/watch?v=W7fPsSw74TM

http://www.youtube.com/watch?v=VMZ9Zy6q6Iw&feature=related

http://www.youtube.com/watch?v=VAJRj8hST1c


SOLVE FOR HOMEWORK!

a.) 10 = x + 6 b.) x + 6 = 8 c.) x - 2 = 9 d.) x - 4 = 5

e.) 2x + 1 = 7 f.) 4x - 2 = 12 g.) x / 4 + 3 = 9 h.) x / 6 - 5 = 1

Tuesday, May 4, 2010

Solving Two-Step Algebraic Equations

Dude pays $19 for 2 t-shirts and a pair of sunglasses. How much does dude pay for each t-shirt?
1.2t + 3=$19
If the sunglasses cost $7 how much are the t-shirts?
2t + 7 =$19
-7 -7
2t + 12
─ ─
2 2
t=6

Check answer:
2(6) +7 = 19
12 +7=19
19+19

Chick saw a sign ,buy two pants and get socks for 4 pairs of socks. If she pays $30 for 2 pants and 4 socks.What is the price of a pair of pants?
Model using blocks on a scale




For short:
2p + 8 = 30
-8 -8
2p + 22
─ ─
2 2
p= 11

Check your answer:
2p+8= 30
2(11) +8+30
22 + 8 = 30
30=30



Now try these:
3w+ 3 =6 2n +4= 10
-3 -3 -4 -4
3w +3 2n = 6
─ ─ ─ ─
3 3 2 2
w = 1 n = 3


To enhance your learning, watch this video!

Embed video for thunder boy.

Here is a video. Enjoy thunder boy.

Monday, May 3, 2010

Solving One Step Algebra Equations

Apply the opposite equation

a+5=7 Step one, isolate the variable
-5 -5 Step two, apply the opposite integer
a=2

a+5=7 The third and final step is to check your answer.
2+5=7
7=7

Easy isn't it? Now that you've learned how to do this, try these questions:
1)b+3=5
2) c/3=7
3)4d=16
Stuck? Well, here are the answers!
HOMEWORK: Pg. 405-407 (questions 1-21)
(text book available here)
If I didn't help, please refer to these videos:
One Step Algebra Equations - Addition
or check this game out:

Thank you for reading my scribe! Please remember to comment below.