Measurement of Central Tendancy

Measures of Central Tendency
- A value that represents the center of a data set
- Can be the mean,median, or mode
Data Set - is a number that you must arrange in order from least to greatest

Median - the middle number in a set of data after the data have been arranged in ordereg.
- median of 2,5,6,8,9 is 6
- median of 1, 3, 6, 8, 9, 10 is 7

Mode - the frequently occurring number in a set of data
mode and most have 4 numbers
- mode of 3,5,7,7,9 is 7
- mode of, 2, 4, 6, 6, 8, 11 is 2 and 6
- mode of 1, 2, 3, 5 is no mode
- mode of 1, 1, 1, 2, 2, 2, 3, 3, 3 is no mode
- mode of 1, 1, 1, 2, 2, 2, 3, 3, 3, 4 is 1, 2 and 3

Mean - a measure of a central tendency, the sum of the set of value divided by the number of values in the set (add up all the numbers, divide that by how many numbers there in the set.)
- mean of 6,4,8 is 6
4,6,8
4+6+8=18

Range - The positive between the largest and smallest values in a data set
- range of 1,3,4,5,5,6,6,8,8,9
9 - 1 = 8
- range of -7, -4, -2, -1
(-1) - (-7) = 6

Outlier - a value that is much larger or smaller then the other data value
the data set may have more then 1 outlier or 0 outliers
outliers are 1,67,67,67,65,100 - 1 and 100

Here is a link/game on calculating median, mode, mean and range
Here is a video:

Equations

Equations - mathematical statement with 2 expressions that have the same value
eg : x+2=3 , y-7 = (-4) , 3a-2 = 9+2 , b=4

Model 8 times a number plus 4 is 12
8n+4 = 12

Identify : 5y-6 = 19
variable = y
numerical coefficient = 5
constant = 6




Opposite Operations
+, -
x , ÷
- , +
÷ , x

a+1 = 3
a+1-1 = 3-1
a = 2

Sub
a+1 = 3
2+1 = 3
3=3



Reverse order of operation

4c-3 = 17
4c-3+3=17+3
4c÷4 = 20÷4
c = 5

Sub
4c-3=17

4(5)-3=17
20-3=17
17=17

here is a game on sovling algebra equations!

here is a video on solving an algebra equation.

Patterns and Expressions Definition

Patterns are arrangements of shapes, colors, numbers, letters, words, and etc. for which you can predict which comes next.

Variable - a letter that represents an unknown number.
eg : x, A, n

Expressions - any single number or variable, or combination of operations ( +, -, x, / ) involving numbers. eg : 5, r, 8t, x+9, 2y, -7

Value - a known or calculated amount

Constant - a number that does not change. Increase or decrease that value of an expression.

Numerical Coefficient - a number that multiples the variable





Linear Relation - a pattern made by two sets of numbers that results in points along a straight line on a coordinate grid
eg :


Graph - a visual way to show how two sets of numbers relate to each other

Relationship - a pattern formed by two sets of numbers

Math game on graphing linear relations

Video :

Answer to Probability Question.

Here is my answer to Kamille's probability question ;

A) Aaron flips a coin and spins a spinner once.

B) Create a tree diagram and a table for these two events.

C) What is the total number of possible outcomes.

* there are eight possible outcomes.

Probability Question.

1)You spin a spinner once with the colors purple, blue, red, and green and roll a 6 sided die.
2)Organize all the possible outcomes for these 2 events.
3)Write the sample space

Perpendicular Bisectors

Bisect - bi and sect

bi - two

sect - cut

bisect - to cut in two

Perpendicular Bisectors

1. Draw a line segment

2. sharp end of compass on point A

3. make an arc slightly larger than half the length of the line segment

4. repeat the process from point B with the same size arc

5. with a ruler join the two arc intersections with a straight line

6. you now have a perpendicular bisector

Another way to make a perpendicular bisector is ;

1. draw a line segment

2. measure with a ruler

3. divide the measurement by two that is the half way point

4. use a right angle triangle to create a perpendicular line at the half way point

The third way is ;

In class today, we also did page 91 in our textbook, only the "show you know"

You had to include all 3 ways of perpendicular bisectors.

We also had to do page 92 in our textbooks. Numbers 1-3

For homework : pages 28-29 in our homework booklet.

Here is a quick video on how to draw a perpendicular bisector of a line :

Here is a link that can help you on perpendicular bisectors.

Order Of Operations

B - brackets

E - exponents

D - division

M - multiplication

A - addition

S - subtract

1) First thing you do is, check if there are any brackets.

2) If there are no brackets, check if there are any exponents if not ;

3) check if there are any division or multiplication. if so, like the example below, you start from left to right, just like the way you read.

4) Then, you check if there are any addition or subtraction. Remember you must start from left, then right.

Homework :

1) Annie has been asked to calculate 1.7 + 6 ÷ 2. She claims the

answer is 3.85. Do you agree? Explain why or why not.

No, because the answer is 3.7 ;

1.7 + 6 ÷ 2 =

1.7 + 3 =

3.7 =

2) Put brackets in the following expression to get the largest value

possible. What problem solving strategy did you use?

3 × 2.8 + 6.4 ÷ 4

division :

3 × 2.8 + (6.4 ÷ 4) =

3 x 2.8 + 1.6 =

8.4 + 1.6 =

10 =

multiplication :

(3 × 2.8) + 6.4 ÷ 4 =

8.4 + 64 ÷ 4 =

8.4 + 1.6 =

10 =

3) Create a problem that could be solved using the following

expression.

2.5 + 1.25 + 5 × 1.6

problem : Max went to a convenient store with $10.00 in his pocket, he wanted to get ;

coke bottle for $2.50

5 packages of candy which was $1.25 each

and a bag of chips for $1.60

would $10.00 be enough ?

answer :

2.5 + 1.25 + 5 × 1.6 =

2.5 + 1.25 + 8 =

3.75 + 8 =

11.75 =

here is a video :

here is a game to help you practice order of operations.

Test Correction For Question 22

Question :
Use the coordinate grid shown to do the following:
a) Rotate ABC 90 degrees in a counter clockwise direction about centre of rotation C.
b) Translate A' B' C' 3 units right and 3 units down.
c) What are the coordinates of B"

Answer :
a) rotated 90 degrees counter clockwise.



















b) translated A' B' C' 3 units right and 3 units down.

















c) (1,0)


; here is a game you can play to practice rotation.