**Mean, Median, Mode**

**Mean**

When you think of averaging, you are most likely to think of finding the mean. You add all of the numbers in the set and divide by how many numbers are in the list

Median

To determine the median, the list of numbers should be arranged in order from lowest to highest. The number in the middle or the average of the two middle numbers is the median.

Mode

Mode refers to the number in a list that occurs most often.

Example Number 1

Example Number 2

In the triangles above, whats is the average (arithmetic mean) of U,V,W,X and Y?

a. 21

b. 45

c. 50

d. 52

e. 54

Lauren Voyles, Ali Sang, Maria Muriel, Shumaq Tahir

Example Number

3

The table above lists the profits of 3 stores in 2 consecutive years. What was the average (arithmetic mean) increase in profit, in dollars, for these 3 stores from year 1 to year 2?

If the average (arithmetic mean) of 6,6,12,16 and X is equal to X, what is the value of X?

a. 6

b. 8

c. 9

d. 10

e. 11

The graph above show the effect of aging on the diameter of the eye pupil. Based on the graph, what is the best estimate of the age at which the average diameter of the aye pupil during the day will equal the average diameter of the eye pupil a night?

a.20 b.30 c.35 d.45 e.60

YEAR 1 YEAR 2

STORE A $5,000 $6,200

STORE B 6,000 7,350

STORE C 10,000 12,700

TOTAL $21,000 $26,000

w'

u'

v'

Y

x

age (years)

diameter (millimeter)

9

8

7

6

5

4

3

2

1

0

20

25

30

35

40

45

50

55

60

DAY

NIGHT