EXAMPLES
1) Find the mean, median, mode and range of the following numbers
3 3 9 1 5 3 8 6 1 4 3 2 8 7 2 4 6 9 8 1 1 3 4 6 9
3 3 9 1 5 3 8 6 1 4 3 2 8 7 2 4 6 9 8 1 1 3 4 6 9
1) To solve this problem, the first step is to rearrange the numbers from ascending to descending order
1 1 1 1 1 2 2 3 3 3 3 3 4 4 4 5 6 6 6 8 8 8 9 9 9
From these value there are two modes 1 and 3. This is because 1 and 3 both occur 5 times.
This term is called a Bimodal
Bimodal - The term used to refer to two modes in statistics
Median - The median is the middle number. Therefore the median is 4
This is because there are 25 numbers in this set, and the 13th value is the middle number
Mean - The average of the number set. To calculate this,
Add up all the numbers and divide by 25
1+1+1+1+1+2+2 +3+3+3+3+3+4+4+4+5+6+6+6+8+8+8+9+9+9 = 110
110/25 = 4.4
Mean = 4.4
Range = Highest number - Lowest number
9 - 1
Range = 8
1 1 1 1 1 2 2 3 3 3 3 3 4 4 4 5 6 6 6 8 8 8 9 9 9
From these value there are two modes 1 and 3. This is because 1 and 3 both occur 5 times.
This term is called a Bimodal
Bimodal - The term used to refer to two modes in statistics
Median - The median is the middle number. Therefore the median is 4
This is because there are 25 numbers in this set, and the 13th value is the middle number
Mean - The average of the number set. To calculate this,
Add up all the numbers and divide by 25
1+1+1+1+1+2+2 +3+3+3+3+3+4+4+4+5+6+6+6+8+8+8+9+9+9 = 110
110/25 = 4.4
Mean = 4.4
Range = Highest number - Lowest number
9 - 1
Range = 8
2) The height of 10 girls in grade 8 are as follows in cm
150, 151, 146, 150, 158, 144, 152, 151, 151, 155
Find the average height of girls in grade 8
Average height means the mean
Therefore we Add up all the number and divide by 10
In this case, we don't need to worry about the arrangement of numbers
150 + 151+ 146 + 150 + 158 + 144 + 152 + 151 + 151 + 155 = 1508
1508/10 = 150.8
Average height = 150.8
150, 151, 146, 150, 158, 144, 152, 151, 151, 155
Find the average height of girls in grade 8
Average height means the mean
Therefore we Add up all the number and divide by 10
In this case, we don't need to worry about the arrangement of numbers
150 + 151+ 146 + 150 + 158 + 144 + 152 + 151 + 151 + 155 = 1508
1508/10 = 150.8
Average height = 150.8
3 ) In a maths test, the average grade was 7, and 10 people wrote the test
What is the total number of marks scored by all the students in the test?
Total number of marks in the test = Sum of all the numbers
However we don't have all the numbers, but the average result for all 10 students
To find mean = Total score/ number of variables
7 = X/10
X = 7 * 10 =70
Total score = 70
What is the total number of marks scored by all the students in the test?
Total number of marks in the test = Sum of all the numbers
However we don't have all the numbers, but the average result for all 10 students
To find mean = Total score/ number of variables
7 = X/10
X = 7 * 10 =70
Total score = 70
EXERCISES
1) What is the name given to the number that occurs the most in a data set
2) How do you find the median number of a data set
3) Find the mode, range, median, mean of this data set
4 6 6 7 1 2 8 9 3 4 2 9 7 6 6 4 3 3 5 1 5 7 3 4 5
4) The number of chocolate sold in a shop over a week are
120 152, 123, 145, 178, 111, 145
Find the mean
5) The average score for 10 exam papers is 72
Find the result of the last exam paper if nine exam papers had scores of
85 67 74 52 64 89 50 78 74
2) How do you find the median number of a data set
3) Find the mode, range, median, mean of this data set
4 6 6 7 1 2 8 9 3 4 2 9 7 6 6 4 3 3 5 1 5 7 3 4 5
4) The number of chocolate sold in a shop over a week are
120 152, 123, 145, 178, 111, 145
Find the mean
5) The average score for 10 exam papers is 72
Find the result of the last exam paper if nine exam papers had scores of
85 67 74 52 64 89 50 78 74