Page 148 - Math Course 2 (Book 2)

Measure of Central Tendency
Mo. 11

Lesson 1 mean

The mean is simply the average, i.e. sum of all the
numbers divided by the number of numbers.

KEY CONCEPTS: Mean
Sum of all values divided by total number of values.
1. Use the mean, median and mode as
measure of central tendency. x
2. Choose an appropriate measure of central x x x x x
x
x
tendency and recognize measure of x x x x x x x
x
x
x
x
x
x
statistics. x x x x x x x x x x
1 2 3 4 5 6 7 8 9 10 11 12
MO. 11 - L1a Source : National Weather Services
Using Mean, Median, mean = 2+3(4)+4(6)+5(5)+6(2)+7(4)+8(3)+9(4)+10+11 ≈5.9
31
and Mode
median
Vocabulary A-Z The median is simply the midpoint of the
distribution, i.e. there are as many numbers
Let us learn some vocabulary above it as below it. The mean of the middle
two numbers.

Median
measures of central tendency Middle value (when the data are arranged in order)
mean, median, and mode are measures of central N + 1/2 Position
tendency to help you capture, with a single number, Median Mean
what is typical of the data.

Sum of all values divided by total
Mean
number of values

Median Middle value (when the data are
arranged in order) mode
Mode Most common value. The mode is simply the most commonly occurring
value.

Central Tendency Measures In a class of 50 students graded on a scale of 1-5,
the distribution may be as shown in the figure. The
mode of this data is 4.
Measure Formula Description

Mean ∑x/n Balance Point
25
Middle Value when
Median n + 1/2 Position 20
ordered
15
Mode None Most frequent
10

5
0
1 2 3 4 5

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