Consider a regulated voltage output, which needs to be checked. Three dc digital bench voltmeters (DVM) are available (red DVM-1, green DVM-2, and blue DVM-3). Find which one provides the best measurement uncertainty, i.e. in the reading result , and provide the value of the uncertainty found only for that DVM.

The first DVM provided the reading , whereas the second shown , and finally, the third gave .

The accuracy performance is summarized below.