HP 32SII Owner's Manual page 153

y–values as weights or frequencies. The weights can be integers or
non–integers.
Example:
Mean (One Variable).
Production supervisor May Kitt wants to determine the average time that a
certain process takes. She randomly picks six people, observes each one as
he or she carries out the process, and records the time required (in minutes):
15.5
12.5
Calculate the mean of the times. (Treat all data as x–values.)
Keys:
{ }
15.5
9.25 10
12 8.5
{ }
Example: Weighted Mean (Two Variables).
A manufacturing company purchases a certain part four times a year. Last
year's purchases were:
Price per Part (x)
Number of Parts (y) 250
Find the average: price (weighted for the purchase quantity) for this part.
Remember to enter y, the weight (frequency), before x, the price.
Keys:
{ }
250 4.25
800 4.6
900 4.7
File name 32sii-Manual-E-0424
Printed Date : 2003/4/24
9.25
12.0
Display:
12.5
$4.25 $4.60 $4.70 S4.10
Display:
Size : 17 .7 x 25.2 cm
10.0
8.5
Description:
Clears the statistics registers.
Enters the first time.
Enters the remaining data;
six data points accumulated.
Calculates the mean time to
complete the process.
800 900 1000
Description:
Clears the statistics registers.
Enters data; displays n.
Statistical Operations 11–5