Finding the Weighted Mean Using the TI-84 and TI-83
Family of Calculators
To find the weighted mean using the TI-84 or TI-83 calculator:
1.) Enter the values into L1 .
STAT 1 for Edit
Type in the data in column 1 under L1 . Press ENTER after each number.
2.) Enter the frequency of occurrence into L2 .
Type in the data in column 1 under L2 . Press ENTER after each number.
Remember if you need to clear a list of data, move the cursor to the top of the
column with the up arrow. When the cursor is on the L1 , press CLEAR
ENTER . You can do the same for L2 .
3.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
Note: The L1 is above the number 1. You will need to press the 2ND button and
then 1 . The L2 is above the number 2. You will need to press the 2ND button and
then 2 . The comma is key above the 7 key.
1
The screens should be:
Examples:
1.) Bill’s Sport Shop had the following sales data for last week. Calculate the
weighted mean.
Value
$400
$100
$80
Frequency
2
3
2
a.) Enter the values into L1 and the frequency of occurrence in L2 .
STAT 1 for Edit
2
b.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
ENTER
The weighted mean is x . Therefore, the mean is 180.
2.) The following table represents Jill’s grades. Calculate her GPA to the nearest
thousandth. Given A = 4; B = 3; C = 2; D = 1; F = 0
Courses
Introduction to Computers
Psychology
English Composition
Business Law
Business Mathematics
Grade = Value
A=4
B=3
B=3
C=2
B=3
Credits = Frequency
4 credits
3 credits
3 credits
3 credits
3 credits
a.) Enter the values into L1 and the frequency of occurrence in L2 .
STAT 1 for Edit
3
b.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
ENTER
The weighted mean is x . Therefore, the mean is 3.063 to the nearest thousandth.
3.) Angie’s Bakery bakes bagels. Find the weighted mean (to the nearest whole
bagel) given the following daily production for June:
200
150
190
360
400
400
150
190
190
400
360
400
200
360
190
400
150
200
150
360
200
150
400
150
200
150
150
200
360
150
4
a.) Tally up the occurrence of each value.
Value
150
190
200
360
400
Frequency
9
4
6
5
6
b.) Enter the values into L1 and the frequency of occurrence in L2 .
STAT
1 for Edit
c.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
ENTER
The weighted mean is x . Therefore, the mean is 250 to the nearest whole number.
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Practice. Answer each of the following.
1.) Find the weighted mean (to the nearest hundredth) for the following:
Value
150
180
240
360
400
Frequency
22
40
16
8
12
2.) The following table represents Thomas’s grades. Calculate his GPA to the
nearest thousandth. Given A = 4; B = 3; C = 2; D = 1; F = 0
Courses
Introduction to Computers
Biology & Lab
English Composition
Physical Education
Business Mathematics
Grade = Value
D=1
B=3
C=2
C=2
A=4
Credits = Frequency
3 credits
4 credits
3 credits
1 credits
5 credits
3.) Roger’s Tree Supply has number of plants sold for June. Find the weighted
mean (to the nearest whole bagel) given the following daily sales for June:
35
60
33
33
60
33
33
60
40
33
60
35
40
40
33
33
35
60
33
60
33
33
40
35
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Answers to Practice
1.)
a.) Enter the values into L1 and the frequency of occurrence in L2 .
STAT 1 for Edit
b.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
ENTER
The weighted mean is x . Therefore, the mean is 224.69 to the nearest hundredths
place.
Answers: 224.69
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2.)
a.) Enter the values into L1 and the frequency of occurrence in L2 .
STAT 1 for Edit
b.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
ENTER
Answer: GPA = 2.688 to the hundredths place
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3.)
a.) Tally up the occurrence of each value.
Value
33
35
40
60
Frequency
10
4
4
6
b.) Enter the values into L1 and the frequency of occurrence in L2 .
STAT 1 for Edit
b.) Now you are ready to calculate the weighted mean. Go to STAT
VAR STATS L1 , L2 ENTER
CALC 1 : 1
ENTER
Answer: The weighted mean (to the nearest whole number) is 41.
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