The lengths of human pregnancies are normally distributed with = 266 days and = 16 days. The area to the right of x = 280 is 0. (a) Find the z value...

The lengths of human pregnancies are normally distributed with μ = 266 days and σ = 16 days. The area to the right of x = 280 is 0.1908.

1. (a) Find the z value based on the given area = 0.1908 from the positive z score table A-2 in the back of the textbook.
2. (b) Interpret the area 0.1908.
3. (c) What is the minimum number of days for the top 10% of pregnant women?
4. (d) What is the maximum number of days for the bottom 5% of pregnant women?

2. The drive-thru times at Tim Horton's are normally distributed with μ = 138.5 seconds

and σ = 29 seconds.

(a) What is the probability that a randomly selected car will get through the drive-thru in less than 100 seconds?

1. (b) What is the probability that a randomly selected car will spend more than 160 seconds in the drive-thru?
2. (c) What proportion of cars spend between 2 and 3 minutes in the drive-thru?
3. (d) Would it be unusual for a car to spend more than 3 minutes in the drive-thru? Why?