1. The information given in the problem is:
- Each arrangement uses 1 vase and 11 orchids.
- Each case cost Marco $4.00.
- C: the total cost of the arrangement.
- r: the cost of 1 orchid.
2. Therefore, you must multiply the cost of 1 orchid by the 11 orchids that he uses in each arrangement, and then, you must add the cost of 1 vase, as below:
C=11r+4
3. Finally, you can conclude that the correct answer is the last option:
D)C=11r+4
