For each color copy, Print Shop X charges $1.20 and Print Shop Y charges $1.70. How much greater is the charge for 40 color copies at Print Shop Y than at Print Shop X?  Choose the correct choice from the following.
A) $ 14
B) $ 16
C) $ 18
D) $ 20
E) $ 22

Rationale: "the difference in the two prices is $ 1.70 - $ 1.20 = $ 0.50 for each color copy . each color copy will cost an extra $ 0.50 at print shop y . 40 * $ 0.50 = $ 20 the answer is d ."
Answer: D