The resent value, also called "discounted value," is the current worth of the camera. So, we know that the discounted value is $105.00.
The first price of the camera was $120.00.
This means that the price is decreased. In order to calculate the discount rate we should find out how many percent the camera was discounted. 105 from 120 is: 105/120*100=87.5
So, the discount is 100-87.5=12.5 %.