Question

11. Rates of on-time flights for commercial jets are continuously tracked by the U.S Department of Transportation. Recently, Southwest Air had the best rate with 80% of its flights arriving on time. A test is conducted by randomly selecting 15 Southwest flights and observing whether they arrive on time. Find the probability that exactly 10 flights arrive on time. (a) .206 (b) .103 (c) .010 (d) .188 (e) .003 12. Refer to question 11. Find the probability that at least 10 flights arrive on time. (a) .939 (b) .061 (c) .854 (d) .759 (e) .093 13. Refer to question 11. Find the probability that at least 5 flights arrive late. (a) 1.00 (b). 836 (c) .939 (d) .164 (e) .836 14. Refer to question 11. Find the probability that 7 or fewer flight arrive late. (a)1.00 (b) .000 (c) .004 (d) .996 (e) .862 show work.

Answer 1

Using Binomial probability law

Let

with n = 15, p = 0.80

then

11.To find

= 0.103

12.

= 0.939

13. Let Y be the number of late arrival ,Y follows Binomial with n =15, p=0.2

.

= 0.164

14.

=0.996