The answer for the exercise is: -2 The explanation is shown below: You have the following function given in the problem above: f(x)=(x-5)³(x+2)². As you can see, (x+2)² is a double root, therefore, it touches the x-axis but it does nos cross it. Therefore, the answer is -2. When you plot the function, you obtain the graph attached.
(2/5) of (2/3) of students = 4/15 of students study French. Then 1-(4/15) = 11/15 of students do not study French. The ratio you want is (4/15):(11/15) = 4:11