The General Manager of a Frozen TV Dinner Maker Must

The general manager of a frozen TV dinner maker must decide which one of four new dinners to introduce to the market. He decides to perform an experiment to help make a decision. Each dinner is sampled by ten people who then rate the product on a 7-point scale, where 1 = poor, and 7 = excellent. The results are shown below. $\begin{array} { | c | c | c | c | c | } \hline & & { \text { Taste Ratings } } \\\hline \text { Respondent } & \text { Dinner 1 } & \text { Dinner 2 } & \text { Dinner 3 } & \text { Dinner 4 } \\\hline 1 & 6 & 6 & 4 & 5 \\\hline 2 & 5 & 5 & 2 & 4 \\\hline 3 & 7 & 7 & 3 & 4 \\\hline 4 & 6 & 6 & 5 & 4 \\\hline 5 & 7 & 6 & 4 & 3 \\\hline 6 & 7 & 5 & 3 & 5 \\\hline 7 & 6 & 4 & 3 & 4 \\\hline 8 & 5 & 6 & 4 & 6 \\\hline 9 & 4 & 4 & 3 & 5 \\\hline 10 & 7 & 5 & 6 & 4 \\\hline\end{array}$ Can the general manager infer at the 5% significance level that there are differences in the taste ratings of the four dinners?