a real estate salesperson bought promotional calendars and date books to give to her customers at the end of the year. The calen
dars cost $0.40 each, and the date book cost $0.75 each. She ordered a total of 300 promotional items and spent $190. How many of each item did she order?
You have to solve two equations simultaneously. The equations are: .40c + .75d =$190 c + d = 300. Multiply this second equation by -0.4 on both sides leaving you -0.40c -0.40d = 120. Subtract this new equation from the first and solve for d. 0.40c + 0.75d = 190 - 0.40c - 0.40d = 120 ----------------------------- 0.35d = 70 Solve for d. 70/0.35d d = 200. Plug this number back into the original equation and c = 100.