Given data:
The given mean life is m=50 months.
The given standard deviation is s=6 months.
The given value of battery life is x= 48 months.
The expression for the probability of that a randomly selected battery will last less than 48 months is,
[tex]\begin{gathered} P(Z<\frac{x-m}{s})=P(Z<\frac{48-50}{6}) \\ =P(Z<-\frac{1}{3}) \end{gathered}[/tex]Refere the Z-table the value of the above expression is 0.3707.
Thus, the probability that a randomly selected battery will last less than 48 months is 0.3707.
