Answer:
0.4082
Step-by-step explanation:
Data
mean ([tex]\mu[/tex]) = 50,000 miles
standard deviation ([tex]\sigma[/tex]) = 12,000 miles
expected distance (X) = 34,000 miles
In the figure attached, standard normal distribution table can be seen. Z is computed as follows:
[tex]Z = \frac{X - \mu}{\sigma}{ [/tex]
[tex]Z = \frac{34000 - 50000}{12000}{ [/tex]
[tex]Z = -1.33{ [/tex]
In standard table, the area between 0 and -1.33 is the sem as between 0 and 1.33. So, the proportion of trucks is 0.4082
