Math Notes

Measures of central Tendency
- A value that represents the centre of a data set
-It can be Mean, Medium or Mode
-A data set is a group of numbers 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 order


If this^ happens, all you have yo do is find out what number is in between the two numbers. So take 6 and 8, You know that 7 is in between so, 7 is our median. Another way to find out the median...
Take the two middle numbers (6 and 8) add them together (6+8) and that would equal 14 right? So, you take 14, and divide it by 2 (14÷2) and that would equal 7, and seven (7) is our Median.


If this^ happens, remember the first thing you do when you get a data, you have to arrange them from least to greatest, after you do that and you get two numbers in the middle and you wanted to find out the Median, remember: take the two middle numbers (3 and 10) add them together (3+10) and that would equal 13 right? So, you take 13, and divide it bye 2 (13÷2) and that would equal 13, and thirteen (13) is our Median.

Mode- the most frequent occuring in a set of data. Here is how you can remember the meaning, MODE and MOST have both 4 letters and they both start in "MO".

(e.g) 3,5,7,7,9
the Mode would be "7" because it's the most occuring number, there are two of them and only one the other numbers.
(e.g) 2,2,4,6,6,8,11
the Mode would be 2 and 6, because there are two and them and they are both tied for having two numbers.
(e.g) 1,1,1,2,2,2,3,3,3
the Mode is nothing because there are three of them for each number.
(e.g) 1,1,1,2,2,2,3,3,3,4
If this happens, the mode this time would be 1,2 and 3, because they are all tied for being first.

Mean- A measure of central tendency. Th sum of a set of values divided by the number of values in the set.





The Mean in this^ image is 6, because the data states 4, 6, and 8, So you take all the numbers in the data (4, 6, and 8) and then add them up (4+6+8) and then that would equal 18 right? So, take 18 and divide it by how much numbers there are in the data, In this data there are 3 numbers, (18÷3) and that would equal to 6, So 6 is our Mean.


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

If this^ happens, always remember when you get a data set, you have to order them from least to greatest, after you do that you take the biggest number (in this situation it's #9) and the smallest number (in this situation it's the #1) and subtract the biggest number to the smallest number (9-1=8) and that would equal to 8, so 8 is our Range.

Outlier- A value that is much longer or smaller than the other data value, the data set may have more than 1 outlier or zero outliers.

The outliers for 1,67,68,67,64,65,100 would be 1 and 100, because the rest of the numbers are somewhere in the 60's and 1 and 100 are so far off.

MATH HOMEWORK FOR TODAY:

Find out the Mean, Mode, Range, Outliers, for the following data set.
1.) 18,19,79,17,20,12

2.)14,14,16,15,1,16

3.)98,202,99,91,2,95,89,88,94

*Here is a LINK where you can learn more facts about Measures of Central Tendency.

*Here is also a link to a VIDEO about Mean, Median and Mode.