HP 35s User Manual page 171

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:
 
()





(  )
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)
Find the average price (weighted for the purchase quantity) for this part. Remember
to enter y, the weight (frequency), before x, the price.
Keys:
 
()






9.25
12.0
Display:



 

$4.25
250
Display:


10.0
8.5
Clears the statistics registers.
Enters the first time.
Enters the remaining data; six
data points accumulated.
Calculates the mean time to

complete the process.
$4.60 $4.70
800 900
Clears the statistics
registers.
Enters data; displays n.
Statistical Operations
Description:
$4.10
1000
Description:
12-5