Question

An advertiser goes to a printer and is charged $38 for 100 copies of one flyer and $50 for 208 copies of another flyer. The

printer charges a fixed setup cost plus a charge for every copy of single-page flyers. Find a function that describes the cost
of a printing job, if x is the number of copies made. C(x) =
4.

Answer 1

C(x) = (1/9)x + 242/9

Explanation:

Let x = number of pages.

Let y = cost.

We are given two ordered pairs, (x, y):

(100, 38) and (208, 50)

We must find the equation of the line that passes through these two points.

y = mx + b

m = (y_2 - y_1)/(x_2 - x_1) = (50 - 38)/(208 - 100) = 12/108 = 1/9

y = (1/9)x + b

Use point (100, 38) as x and y to find b.

38 = (1/9)(100) + b

38 × 9 = 100 + 9b

9b + 100 = 342

9b = 242

b = 242/9

The equation is:

y = (1/9)x + 242/9

Answer: C(x) = (1/9)x + 242/9