Students entering a certain university have historically selected the following programs;

Business - 10%

Education - 25%

Engineering - 30%

Liberal Arts - 25%

Science - 10%

Data obtained for the most recent class show that 73 students selected business, 105 selected education, 150 selected engineering, 124 chose liberal arts and 47 chose science. At the 10% level is there evidence that the historical percentages have changed? Use Critical Value(s).

*I am quite confused about how to go about the whole question and especially about critical values so if you could really explain that, it would be more helpful*