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Null hypothesis:female professors and male professors have the same mean evaluation ratings.

\({H_0}\):\({\mu _1} = {\mu _2}\).

Alternative hypothesis:female professors and male professors do not have the same mean evaluation ratings.

\({H_1}\):\({\mu _1} \ne {\mu _2}\).

Here, \({\mu _1},{\mu _2}\)are population mean evaluation ratings of female and male professors respectively

The sample mean of female professors is given by,

\(\begin{array}{c}{{\bar x}_1} = \frac{{\sum\limits_{i = 1}^{{n_1}} {{x_i}} }}{{{n_1}}}\\ = \frac{{4.4 + 3.4 + 4.8 + .... + 4.8}}{{10}}\\ = 4.02\end{array}\)

Therefore, the mean value of \({\bar x_1} = 4.02\)

The sample mean of male professors is given by,

\(\begin{array}{c}{{\bar x}_2} = \frac{{\sum\limits_{i = 1}^{{n_2}} {{x_i}} }}{{{n_2}}}\\ = \frac{{4.0 + 3.6 + 4.1 + .... + 4.3}}{{10}}\\ = 4.1\end{array}\)

The standard deviation for female professors is given by,

\(\begin{array}{c}{s_1} = \sqrt {\frac{{\sum\limits_{i = 1}^{{n_1}} {{{({x_i} - {{\bar x}_1})}^2}} }}{{{n_1} - 1}}} \\ = \sqrt {\frac{{{{\left( {4.4 - 4.02} \right)}^2} + {{\left( {3.4 - 4.02} \right)}^2} + .... + {{\left( {4.8 - 4.02} \right)}^2}}}{{10 - 1}}} \\ = 0.7208\end{array}\)

Therefore, the standard deviation is\({s_1} = 0.7208\)

The standard deviation for male professors is given by,

\(\begin{array}{c}{s_2} = \sqrt {\frac{{\sum\limits_{i = 1}^{{n_2}} {{{({x_i} - {{\bar x}_2})}^2}} }}{{{n_2} - 1}}} \\ = \sqrt {\frac{{{{\left( {4.0 - 4.1} \right)}^2} + {{\left( {3.6 - 4.1} \right)}^2} + .... + {{\left( {4.3 - 4.1} \right)}^2}}}{{10 - 1}}} \\ = 0.3528\end{array}\)

Therefore, the standard deviation is \({s_2} = 0.3528\)

When two samples are independent and have an equal but unknown standard deviation, use a t-test for two samples.

The test statistic is given by,

\(\begin{array}{c}t = \frac{{\left( {{{\bar x}_1} - {{\bar x}_2}} \right) - \left( {{\mu _1} - {\mu _2}} \right)}}{{\sqrt {\frac{{s_1^2}}{{{n_1}}} + \frac{{s_2^2}}{{{n_2}}}} }}\\ = \frac{{\left( {4.02 - 4.1} \right) - \left( 0 \right)}}{{\sqrt {\frac{{{{0.7208}^2}}}{{40}} + \frac{{{{0.3528}^2}}}{{40}}} }}\\ = - 0.3152\end{array}\)

Calculated value of test statistic is -0.315.

Degrees of freedom:

\(\begin{array}{c}\left( {{n_1} - 1} \right) = \left( {10 - 1} \right)\\ = 9\end{array}\)

\(\begin{array}{c}\left( {{n_2} - 1} \right) = \left( {10 - 1} \right)\\ = 9\end{array}\)

Degrees of freedom is the minimum of two values, which is 9.

The two-tailed test has two critical values.

Refer to the t-table for two-tailed test with a 0.05 level of significance and 9 degrees of freedom.

The critical value is given by,\({t_{\frac{{0.05}}{2}}} = 2.262\)

Thus, the critical value are \( \pm 2.262\)

The decision rule,

If\(\left| t \right| > {t_{\frac{\alpha }{2}}}\), reject the null hypothesis. Otherwise fail to reject the null hypothesis.

In this case, 0.315 < 2.262, which implies that the null hypothesis is failed to be rejected.

Thus, there is enough evidence to support the null hypothesis that both female and male professors have the same mean evaluation ratings.

Therefore, there does not appear to be any difference between the evaluation scores of two professors.