Empirical Rule Question

The author's Generac generator produces voltage amounts with a mean of 125.0 volts and a standard deviation of 0.3 volt, and the voltages have a bell-shaped distribution. Using the empirical rule, what is the approximate percentage of voltage amounts between

a. 124.4 volts and 125.6 volts

b. 124.1 volts and 125.9 volts

Sedrak

a. 124.4 volts and 125.6 volts

This interval is +/- 2 standard deviation and according to the Empirical Rule ...

approximate percentage = 95%



b. 124.1 volts and 125.9 volts


This interval is +/- 3 standard deviation and according to the Empirical Rule ...

approximate percentage = 99.7%


hope that helped