Question

A bookstore rents books to students for $2 per book. The cost of running the bookstore is $300 per hour. The numbers of books and the probabilities that the bookstore would rent them in an hour mimics the distribution of the outcomes of flipping four coins. The probability of renting a number of books was observed to be the same as the number of heads that appear in a four-coin flip. This distribution is represented in the table.

Books Rented Probability
0 1/16
1 4/16
2 6/16
3 4/16
4 1/16

If its only income came from book rentals, the bookstore would have to rent books to
students each hour, on average, to break even.

Answer 1

If its only income came from book rentals, the bookstore would have to rent books to_____
students each hour, on average, to break even.

Answer 2

what are the options to fill in the blank?

Answer 3

I have to type it myself

Answer 4

ah okay, so for 1 student, 1 book is 2$. the bookstore makes 300$ an hour, i think there asking how much books are sold to [?] amount of students an hour to make 300$ if im correct.

Answer 5

yes

Answer 6

hmm. so divide 300 by 2, that should equal 150. 150 students should come in each hour and rent atleast a book per person. so the answer should be 150 if im correct.

Answer 7

dont know if im correct or not but thats atleast what i think there asking

Answer 8

We need to calculate the expected number of books rented based on the probability table

For each probability, multiply (books rented)*(probability of that number)

So starting with the first row, multiply 0 books *(1/16) to get 0

Repeat with the other rows in the table

Sum the products.

The result is the expected number of books per person.

Each book costs $2 to rent, so hourly revenue = 2*(I expected number of books per person).

Finally, the break-even point must be # of students = (300)/(2*expected number of books per person)