Calculating Average

[Thomas Emmanuel Datong]

Cell A1 has 30
Cell C1 has -
Cell E1 has 50
How do I calculate in cell C10 the average of the three cells using either sumifs/countifs or a better way-out please

 

[Kerryx]

Book1
	A	B	C	D	E
1	30		-		50
2
3
4
5
6
7
8
9
10			40
Sheet1

Cell Formulas
Range	Formula
C10	C10	=AVERAGE(A1,C1,E1)