TABLE 11-9
the Marketing Manager of a Company $\quad$

TABLE 11-9
The marketing manager of a company producing a new cereal aimed for children wants to examine the effect of the color and shape of the box's logo on the approval rating of the cereal. He combined 4 colors and 3 shapes to produce a total of 12 designs. Each logo was presented to 2 different groups (a total of 24 groups) and the approval rating for each was recorded and is shown below. The manager analyzed these data using the ? = 0.05 level of significance for all inferences.
$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\text { COLORS }$
$\begin{array} { l l l l l } \text { SHAPES } & \text { Red } & \text { Green } & \text { Blue } & \text { Yellow } \\ \text { Circle } & 54 & 67 & 36 & 45 \\ & 44 & 61 & 44 & 41 \\ \text { Square } & 34 & 56 & 36 & 21 \\ & 36 & 58 & 30 & 25 \\ \text { Diamond } & 46 & 60 & 34 & 31 \\ & 48 & 60 & 38 & 33 \end{array}$

$\text { Analysis of Variance }$
$\begin{array}{lrcrrr}\hline \text { Source } & d f & {S S} & {\text { MS }} & {F} & p \\\hline \text { Colors } & 3 & 2711.17 & 903.72 & 7230 & 0.000 \\\text { Shapes } & 2 & 579.00 & 289.50 & 23.16 & 0.000 \\\text { Interaction } & 6 & 150.33 & 25.06 & 2.00 & 0.144 \\\text { Error } & 12 & 150.00 & 12.50 & & \\\text { Total } & 23 & 3590.50 & & &\end{array}$

-Referring to Table 11-9, the mean square for error is ____.