Consider the dc output voltage measurement of a device under test (DUT), which consists on a voltage regulator, as shown in figure. In order to obtain the voltage output for a given load , a 4  digital multimeter (DMM) was used as a voltmeter, always selecting the most adequate measurement range for the readings.

A large number of independent voltage readings has been performed, , leading to the average value , with standard deviation .

Obtain the absolute value for the expanded combined uncertainty (from types A and B uncertainties) at a 95 % confidence interval.

The DMM manufacturer provides the accuracy of the voltmeter in the table below.