You are asking for the second part (part b) of a problem and some needed information is missed.
The relevant information missed is the amound of problems that the professor assigned and the number of problems that were going to be selected to grade.
When you have that information you can use combinatory theory to find the amount of different groups of problems that can be formed under the given conditions, and then the probability that the group done by the student is exactly the group selected by the professor.
Suppose that the missing information is that the professor grades 6 problems out of 15 to grade.
Then the number of possible groups of 6 out of 15 problems is:
Jessica pays a membership fee of $40
so that's given to us
<span>Jessica has a membership fee of $40 (given) Nancy has a membership fee of $30 (y intercept of the equation) </span>so how much is jessica going to pay is $10 more than Nancy
The area of the triangle above will equal one half of a rectangle that is 5 units long and 3 units wide. The area of the triangle is 7.5 units and the area of the rectangle is 15 units
