See if this example gets you headed in the right direction:

A1: Name
B1: Quiz
C1: Quiz
D1: Exam

F1: QuizAvg
G1: ExamAvg
H1: Wtd Avg
I1: QuizWt
J1: ExamWt

F2: =SUMPRODUCT(--($B$1:$D$1="Quiz")*$B2:$D2)/COUNTIF($B$1:$D$1,"Quiz")
G2: =SUMPRODUCT(--($B$1:$D$1="Exam")*$B2:$D2)/COUNTIF($B$1:$D$1,"Exam")
H2: =F2*I2+G2*J2
I2: 40%
J2: 60%

Now just enter names and grades.

Example:
Bill, 80, 80, 90
QuizAvg: 80
ExamAvg: 90
WtdAvg: 86

Does that help?

***********
Regards,
Ron

XL2002, WinXP-Pro


"Gage Teacher" wrote:

How do I weight a cell in an array of cells that I want to average?
Specifically, I want to give more weight to the final exam than to the unit
tests. Sum and Sumproduct don't seem to apply.