Question

The number of passengers on the Carnival Sensation during one-week cruises in the
Caribbean follows the normal distribution. The mean number of passengers per cruise is
1,820 and the standard deviation is 120.

a. What percent of the cruises will have between 1,820 and 1,970 passengers?
b. What percent of the cruises will have 1,970 passengers or more?
c. What percent of the cruises will have 1,600 or fewer passengers?
d. How many passengers are on the cruises with the fewest 25 percent of passengers?

Answer 1

Try using the computional tool at this website:
http://psych.colorado.edu/~mcclella/java/normal/accurateNormal.html

Enter the mmean and the std. dev., and the limits of the integration interval, and then click "enter". Here are the answers I get:
(a) 39.4%
(b) 10.6%
(c) 3.3%
(d) 1739 passengers or less make up 25% of the sailings

Answer 2

Thank you