The following is a list of
5
measurements.
18
,
5
,
11
,
8
,
6
Send data to calculator
Suppose that these
5
measurements are respectively labeled
x1
,
x2
,
…
,
x5
. Compute the following.
Σ=i15xi
To compute the sum of the measurements, Σ(xi), we sum up all the values provided:
Σ(xi) = 18 + 5 + 11 + 8 + 6 = 48
The following is a list of
5
measurements.
5
,
17
,
13
,
17
,
6
Send data to calculator
Suppose that these
5
measurements are respectively labeled
x1
,
x2
,
…
,
x5
. Compute the following.
Σ=i15xi2
To compute the sum of the squared measurements, Σ(xi^2), we square each measurement and then sum up the squared values:
Σ(xi^2) = (5^2) + (17^2) + (13^2) + (17^2) + (6^2)
= 25 + 289 + 169 + 289 + 36
= 808
The following is a list of
5
measurements.
6
,
13
,
10
,
19
,
10
Send data to calculator
Suppose that these
5
measurements are respectively labeled
x1
,
x2
,
…
,
x5
. Compute the following.
Σ=i15xi
To compute the sum of the measurements, Σ(xi), we sum up all the values provided:
Σ(xi) = 6 + 13 + 10 + 19 + 10 = 58
Here are the numbers of children in 16 elementary school classes.
20
,
17
,
18
,
19
,
16
,
17
,
17
,
20
,
18
,
16
,
18
,
20
,
17
,
20
,
19
,
18
Send data to calculator
Find the modes of this data set.
If there is more than one mode, write them separated by commas.
If there is no mode, click on "No mode."
To find the modes of a data set, we look for the values that appear most frequently.
In this case, the modes of the data set {20, 17, 18, 19, 16, 17, 17, 20, 18, 16, 18, 20, 17, 20, 19, 18} are:
17, 18, and 20
These three values appear most frequently in the data set.
The following list gives the number of public libraries in each of 13 cities.
11
,
8
,
7
,
8
,
7
,
11
,
10
,
9
,
9
,
7
,
7
,
8
,
9
Send data to calculator
Find the modes of this data set.
If there is more than one mode, write them separated by commas.
If there is no mode, click on "No mode."
To find the modes of the data set {11, 8, 7, 8, 7, 11, 10, 9, 9, 7, 7, 8, 9}, we need to determine the values that occur most frequently.
In this case, the modes of the data set are:
7 and 8
Both of these values appear most frequently, so they are considered the modes of the data set.
The test scores of the students in four classes are summarized below. Answer the questions about them.
Class A: The mean score is
103
and the range of scores is
39
.
Class B: The mean score is
106
and the range of scores is
41
.
Class C: The mean score is
112
and the range of scores is
43
.
Class D: The mean score is
111
and the range of scores is
48
.
(a) Based on the information above, which class has the highest scores on average?
Class A
Class B
Class C
Class D
(b) Based on the information above, which class's scores have the most variability?
Class A
Class B
Class C
Class D