A manufacturer of souvenir items makes key rings which sell for $5.80 each. The cost of manufacturing is $1250 to set up the process, and then $0.80 per key ring.

Question

1) Write a rule for the income in dollars, S, from selling n of these key rings.
2) Write a rule for the profit in dollars, P, from selling n of these key rings.
3) Find the number of key rings that must be sold to break even.

Answer 1

1. Y = 5.80n.

2. P = 5.80n - 0.8n - 1250,
P = 5n - 1250.

3. P = 5n - 1250 = 0,
n = 250.