7. The medical records of infants delivered at the Kaiser Memorial Hospital show that the

infants' lengths at birth (in inches) are normally distributed with a mean of 21 and a standard

deviation of 2.6. Find the probability that an infant selected at random from among those

delivered at the hospital measures is more than 23inches.

a. 0.7692

b. 0.1991

c. 0.9458

d. 0.2206

e. 0.6579

For problems 8- 10, use the appropriate normal distribution to approximate the resulting

binomial distributions.

8. A coin is weighted so that the probability of obtaining a head in a single toss is 0.3. If the coin

is tossed 35 times, what is the probability of obtaining between 9 and 14 heads, exclusive.

a. 0.510

b. 0.627

c. 0.701

d. 0.287

e. 0.824

9. If 14% of men are bald, what is the probability that more than 100 in a random sample of 850

men are bald?

a. 0.9778

b. 0.9664

c. 0.0697

d. 0.0027

e. 0.0378

10. The Colorado Mining and Mineral Company has 1000 employees engaged in its mining

operations. It has been estimated that the probability of a worker meeting with an accident during

a 1-yr period is 0.08. What is the probability that more than 70 workers will meet with an

accident during the 1-yr period?

a. 0.8665

b. 0.9089

c. 0.3585

d. 0.3827

e. 0.6548