Mrs. Zabel, the yearbook adviser, always likes to sell a large amount of yearbooks because after the initial set-up costs are paid, the printing is not too expensive.

If the yearbook staff sells 50 yearbooks, the cost per yearbook is $45. If they sell 125 yearbooks, the cost per yearbook is $37.50.

Assuming a linear equation fits the situation, find the price per yearbook if the staff sells 150 yearbooks.

Question

Mrs. Zabel, the yearbook adviser, always likes to sell a large amount of yearbooks because after the initial set-up costs are paid, the printing is not too expensive.

If the yearbook staff sells 50 yearbooks, the cost per yearbook is $45. If they sell 125 yearbooks, the cost per yearbook is $37.50.  

Assuming a linear equation fits the situation, find the price per yearbook if the staff sells 150 yearbooks.

mathstudent55 · Answer

Use ordered pairs (50, 45) and (125, 37.50) to find the equation of the line that passes through those two points. Then plug in 150 for x and calculate y.