## mean of data.

If you have 7 sets of numbers
$
\left (4,4,3,3 \right )=A$

$\left (NA,NA,4,4 \right )=B$
$\left (4,3,4,2 \right )=C$
$\left (4,4,4,5 \right )=D$
$
\left (3,3,4,4 \right )=E$

$\left (2,4,3,3 \right )=F$
$\left ( 4,4,4,4 \right )=G$

If we find the mean each set, then find the mean of all the sets to that:
(S=total # of sets M=mean)

$\frac{A+B+...+G}{S}=M$

How would we account for the two missing values in B?
Would it be wrong to only use the two values?