FIGURE 21- Find the value of A(z)
Refer to the table of areas under the normal probability curve, and take the absolute value
of z. If z =1.10, ,4(z) = 0.364. - Compute the required probability
The area under consideration lies to the left of a vertical line at X= 5.25, and the area
found in step 2 lies between this line and the centerline. Then P(X< 5.25) = 0.5 - 0.364 =
0.136.
NEGATIVE-EXPONENTIAL DISTRIBUTION
The mean life span of an electronic device that operates continuously is 2 months. If the
life span of the device has a negative-exponential distribution, what is the probability that
the life span will exceed 3 months?