Descriptive Statistics

Question 1

Calculate the mean of 2, 5, 6, 7, 10

Answer 1

2+5+6+7+10=30
Total numbers added = 5
30/5=6

Question 2

Calculate the mode (most often) of 2,5,2,9,6,11,2

Answer 2

2 occurs most often

Question 3

Calculate the median (one in the middle) of
4, 5, 10, 12, 14

Answer 3

10

Question 4

Calculate the median of
6, 2, 45, 27, 63, 52

Answer 4

Put them in order first:
2, 6, 27, 45, 52, 63

Divide the 2 scores in the middle by 2 (27+45)/2 = 36

Question 5

Calculate the range ( highest score minus lowest score) of
6, 10, 35, 50

Answer 5

50 - 6 = 44

Question 6

Calculate the interquartile range (IQR) of
3 3 4 5 6 8 10 13 14 16 19

Answer 6

First find the median (8)

Then find the median of the numbers below this (4)

Then find the median of the numbers above 8 (14)

IQR = 14 - 4 = 10

Question 7

What is the Standard Deviation of
5, 9, 10, 11, 15

Answer 7

First work out the mean = 10

Take each number and take 10 away from it then sqare it:
(5-10) squared = 25
(9-10) squared = 1
(10-10) squared = 0
(11-10) squared = 1
(15-10) sqared = 25

Add all these numbers up = 52

Divide by the amount of numbers you started with (5)
52 / 5 = 10.4

Find the square root of 10.4 = 3.22