Mean median mode_range

Upload
farhanashaheen 
Category
Education

view
134 
download
0
Transcript of Mean median mode_range
Mean, Median, Mode are all types of average. An
average summarises groups of data.
Mean – The average of a group of numbers.
2, 5, 2, 1, 5Mean = (2+5+2+1+5)/5 =3
Mean is found by evening out the numbers
2, 5, 2, 1, 5
Mean is found by evening out the numbers
mean = 3
Exercises: Find the mean of the following data:
1) 8, 10, 12, 18, 22, 26
2) 7, 10, 16
3) 2, 9, 14, 27
4)1, 2, 7, 11, 19
Average often means the ‘mean’
Mean = total of the numbers divided by how many numbers.
Class shoe sizes: 3, 5, 5, 6, 4, 3, 2, 1, 5, 6
Add up the numbers:
3 + 5 + 5 + 6 + 4 + 3 + 2 + 1 + 5 + 6 = 40
Divide by how many numbers:
40 ÷ 10 = 4
The class mean shoe size is 4
Definition
Median
is in the
Middle
Median – The middle number in a set of ordered numbers.
1, 3, 7, 10, 13
Median = 7
16, 10, 7
Median=10
Solution:7, 10 , 16
29, 8, 4, 11, 19
Median=11
Sol:4,8, 11, 19, 29
Note : If there are two middle numbers, find the median of these two numbers.
18, 19, 21, 25, 27, 28
232
2521
median
31, 7, 2, 12, 14, 19
2, 7, 12, 14, 19, 31Median=12 + 14 = 26
132
26
1) 53, 5, 81, 67, 25, 78
2) 3,5,4,6,10,5,6,9,23) 5,2,3,6,4,4,3,54)16,7,2,6,4,1,7,1,1,1,3,2,11,1,
5,1,4,12
Median is the middle value
Put the numbers in order
Choose the number in the middle of the list.
If there are 2 numbers in the middle then it is halfway between them.
Class shoe sizes: 3, 5, 5, 6, 4, 3, 2, 1, 5, 6
Put in order: 1, 2, 3, 3, 4, 5, 5, 5, 6, 6
The class median shoe size is 4.5
Mode
is the most
Popular number
Mode – The number that appears most frequently in a set of numbers.
1, 1, 3, 7, 10, 13
Mode = 1
Step 1 – Arrange the numbers in order from least to greatest.
21, 18, 24, 19, 18
29, 8, 4, 8, 19
Mode=8
Sol: 4, 8, 8, 19, 29
1, 2, 2, 9, 9, 4, 9, 10
Mode=9
1, 2, 2, 4, 9, 9, 9, 10
22, 21, 27, 31, 21, 32
Mode=21
21, 21, 22, 27, 31, 32
Mode is the most common number
Put the numbers in order
Choose the number that appears the most frequently.
Sometimes there may be more than one mode.
Class shoe sizes: 3, 5, 5, 6, 4, 3, 2, 1, 5, 6,6
Put in order: 1, 2, 3, 3, 4, 5, 5, 5, 6, 6, 6
The class modal shoe size is 5,6.
Step 2 – Find the number that is repeated the most.
18, 18, 19, 15, 15, 21,12,16,17, 24,18, 19, 19
Mode=18, 19
1) 53, 5, 81, 67, 25, 78
2) 3,5,4,6,10,5,6,9,23) 5,2,3,6,4,4,3,54)16,7,2,6,4,1,7,1,1,1,3,2,11,1,
5,1,4,12
Range
is the distance
Between
Range – The difference between the greatest and the least value in a set of numbers.
1, 1, 3, 7, 10, 13Range = 131=12
Range is how far from biggest to smallest.
Put the numbers in order
Take the smallest number from the largest.
Class shoe sizes: 3, 5, 5, 6, 4, 3, 2, 1, 5, 6
Put in order: 1, 2, 3, 3, 4, 5, 5, 5, 6, 6
Subtract smallest from largest: 6 – 1 = 5
Range: 5
Step 1 – Arrange the numbers in order from least to greatest.
21, 18, 24, 19, 27
Step 2 – Find the lowest and highest numbers.
18, 19, 21, 24, 27
Step 3 – Find the difference between these
two numbers.
27 – 18 = 9The range is 9
29, 8, 4, 8, 19
Range=29 – 4 = 25
4, 8, 8, 19, 29
22, 21, 27, 31, 21, 32
32 – 21 = 11
21, 21, 22, 27, 31, 32
31, 8, 3, 11, 19
31 – 3 = 28
Sol:3, 8, 11,19, 31
23, 7, 9, 41, 19
41 – 7 = 34
7, 9, 23, 19, 41