Question

the teachers editions of a statistics textbook sell for $150 each, and students editions of the book sell for $50 each. which function can be used to find the average cost per book if two teachers editions and x students editions are purchased? \\( f(x)=\frac{150 + 50x}{1 + x} \\) \\( f(x)=\frac{150 + 50x}{2 + x} \\) \\( f(x)=\frac{300 + 50x}{1 + x} \\) \\( f(x)=\frac{300 + 50x}{2 + x} \\)

Explanation:

Step1: Calculate total cost of teacher editions

Total cost for 2 teacher editions: $2 \times 150 = 300$

Step2: Calculate total cost of student editions

Total cost for $x$ student editions: $50x$

Step3: Calculate total cost of all books

Total cost = $300 + 50x$

Step4: Calculate total number of books

Total books = $2 + x$

Step5: Find average cost function

Average cost = $\frac{\text{Total Cost}}{\text{Total Number of Books}}$
$\bar{f}(x) = \frac{300 + 50x}{2 + x}$

Answer:

$\bar{f}(x)=\frac{300+50x}{2+x}$ (the fourth option)