Consider the measurement of the DC output voltage of a device under test (DUT), which consists of a voltage regulator, as shown in the figure. 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 were taken, with . This resulted in an average value and a standard deviation .

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

The DMM manufacturer’s accuracy for the DC voltmeter is provided in the table below.