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