For this problem, we're finding the percent of 300. To do that we:
1. Multiply 300 by 15.
300 x 15 = 4500
2. Divide 4500 by 100. (% = 100)
4500 / 100 = 45
Therefore, the unit price is 45. But we're not done. We need to subtract 45 by 300.
300 - 45 = 255
Now, our answer is 255 and the unit price is 45.
Let me know of any questions!