HP 33s 11–5, Price per Part (x), Number of Parts (y), Statistical Operations 11–5, Example: Weighted Mean (Two Variables)

15.5	9.25	10.0
12.5
	12.0	8.5

Calculate the mean of the times. (Treat all data as x–values.)

Keys:Display:Description:

{c{´}				
15.5				)
9.25	10 12.5  
12 8.5 				)
										· 
{			}				¸		º
		º			º
				)

Clears the statistics registers.

Enters the first time.

Enters the remaining data; six data points accumulated.

Calculates the mean time to complete the process.

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)	$4.25	$4.60	$4.70	$4.10
Number of Parts (y)	250	800	900	1000

Find the average price (weighted for the purchase quantity) for this part. Remember to enter y, the weight (frequency), before x, the price.

	Keys:						Display:				Description:
{c{´}											Clears the statistics
											registers.
￿ 250	‘4.25 										Enters data; displays n.
￿ 800	‘4.6 			
￿ 900	‘4.7 			)
				)
￿ 1000 ‘4.1 				8)							Four data pairs
				)							accumulated.
{			· }		º		¸			· 	Calculates the mean
									º
		º
				)							price weighted for the
											quantity purchased.

Statistical Operations 11–5