Answer:
99.7%
Step-by-step explanation:
Mean number of passengers (μ) = 180 passengers
Standard deviation (σ) = 20 passengers
The number of standard deviation from the mean for the lower and upper bounds of the 120 to 240 passengers intervals are:
[tex]L = \frac{180-120}{20} =3\\U = \frac{240-180}{20} =3[/tex]
Therefore, all of the data is within 3 standard deviations from the mean. According to the empirical rule, 99.7% of the data is within 3 standard deviations from the mean. Therefore, we can assert with a 99.7% probability that there will be between 120 and 240 passengers.
