Bunuel
The county-mandated guidelines at a certain community college specify that for the introductory English class, the professor may choose one of three specified novels, and choose two from a list of 5 specified plays. Thus, the reading list for this introductory class is guaranteed to have one novel and two plays. How many different reading lists could a professor create within these parameters?
A. 15
B. 30
C. 90
D. 150
E. 360
Kudos for a correct solution. MAGOOSH OFFICIAL SOLUTION:There are three possibilities for the novel. With the plays, we are taken a combination of 2 from a set of 5 --> n = 5, r = 2, n – r = 3
# of combinations = \(\frac{5!}{2!3!} = \frac{(5)(4)(3)(2)(1)}{(2)(1)(3)(2)(1)} = \frac{(5)(4)}{2} = 10\)
If the plays are P, Q, R, S, and T, then the 10 sets of two are PQ, PR, PS, PT, QR, QS, QT, RS, RT, & ST.
Any of the three novels can be grouped with any of the 10 possible pairs of plays, for a total of 30 possible reading lists.
Answer: B.