Question 1: The length of human pregnancies from conception to birth varies according to a distribution ...

Question 1: The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with a mean of 266 days and standard deviation of 16 days.

• What percent of      pregnancies last less than 240 days?
• What percent of      pregnancies last between 240 days and 270 days?
• How long do the      longest 20% of pregnancies last?

Question 2: A federal report find that a lie detector test given to truthful persons have a probability of 0.2 of suggesting that the person is deceptive. A company asks 12 job applicants to take a lie detect test.  Suppose that all 12 applicants answer truthfully.

• What is the      probability that exactly one is being deceptive.
• What is the      probability that at most one is being deceptive.
• What is the mean      and standard deviation of this distribution.