A voltmeter indicates that the potential at a location between two parallel conducting plates is $12\mathrm{.}6$ V $,$ where the negatively charged plate is at $0$ V $.$ If the plates are $22$ mm apart and are connected to a $20-V$ battery, how far is the measurement location from the negative plate? Report your answer is units of millimeters. For example, if your calculations produce a value of $1\mathrm{.}23$ mm $,$ enter your answer as $1\mathrm{.}23.$