Statistics name: Myztique and Anna
WALT Identify the mean, median and mode within a collection of data
Activity One
Answer the questions in a different colour
The definition of the mean in a statistical investigation is commonly referred to as the average. It is the total of all the data divided by the amount of data shown.
For example: if we have this range of data 3,5,7,1,2,3,6,8
3+5+7+1+2+3+6+5 = 32 = 4
8 8
Find the mean in this set of numbers
3+7+8 +4+2+6+5+4+3+9 = 51 ➗ 10 = 5 r 1
Find the mean in the set of numbers
4+12+5+6+11+9+5 = 52 ➗ 7 = 7 r 3
Find the mean in this tally chart
Pets owned by students

Number of students

Dogs

IIIII IIIII

Cats

IIIII IIIII II

Fish

IIII

Rabbits

II

10 + 12 + 4 + 2 = 28 ➗ 4 = 7
Find the mean in this set of numbers
24+12+16+18 = 70 ➗ 4 = 17 r 2
Find the mean in this set of numbers
5+9+12+4+10+7= 47 ➗ 6 = 7 r 5
CHALLENGE QUESTION: Find the mean within this data, use the frequency table to help you
1+5+5+2+1+2+5+5+5+5+1+2+1+5+5 = 50 ➗ 15 = 3 r 5
Score

Frequency

1

4

2

3

5

8

Total

15

Activity Two
Answer the questions in a different colour
The definition of the median is the middle number within a set of numbers that have been put in order from size (biggest to smallest or smallest to biggest)
For example: 2,6,4,1,9 = 1,2,4,6,9 and the middle number is 4.
BUT say if there is more than one middle number… the median is found by taking the number midway between the middle pair of numbers:
3,6,1,4,9,2 = 1,2,3,4,6,9 → 3 + 4 = 3.5
2
Find the median in these sets of numbers
10,14,17,12,19,11,16
10,11,12,14,16,17,19  the middle number is 14
34,42,37,31,40
31, 34,37,40,42  the middle number is 37
101, 167,138,124,198,149
101, 124, 138,149, 167, 198  the middle number is 143.5
54, 58,52,57,53,60
53,53,54,57,58,60  the middle number is 55.5
1001, 1094, 1023, 1065, 1038, 1027, 1042
1001, 1023, 1027, 1038, 1042, 1065, 1094  the middle number is 1038
Find the median within this tally chart
Pets owned by students

Number of students

Dogs

IIIII IIIII

Cats

IIIII II

Fish

IIII

Rabbits

IIIII III

Hamsters

II

2 ,4, 7, 8 , 10 = 7
Activity Three
The mode is the most frequent number in a set of data. The number that occurs most often.
For example: In a set of numbers 3, 7, 8, 4, 2, 6, 5, 4, 3, 9 there is two modes, 3 and 4 because they appear twice in the data set.
Note There can either be 0, 1 or 2 modes. If there are 3 or more numbers occur the same number of times, there is no mode.
Find the mode in these sets of numbers
2, 1, 5, 3, 7, 8, 5, 3 ,9 = 3 and 5
1, 5, 3, 2, 9 ,4, 1, 6, 8, 0 = 1
23, 45, 78, 12, 45, 67, 32, 46, 93, 12 = 12 and 45
101, 121, 123, 145, 167, 121, 139, 145, 176 = 121 and 145
394, 273, 219, 294, 183, 291, 273, 288, 271 = 273