Multiple choice questions on probability

EXHIBIT 4: The student body of a large university consists of 60% female students. A random sample of 8 students is selected.

(1) Refer to Exhibit 4. What is the probability that among the students in the sample exactly two are female?
a. 0.0896
b. 0.2936
c. 0.0413
d. 0.0007
e. None of the above __________

(2) Refer to Exhibit 4. What is the probability that among the students in the sample at least 6 are male?
a. 0.0413
b. 0.0079
c. 0.0007
d. 0.0499
e. None of the above ___________

EXHIBIT 5: The credit card balance of one elderly group is normally distributed with a mean of $200 and a standard deviation of $25.

(3) Referring to Exhibit 5, the probability of an elderly person from this group having a credit card balance of more than $241.25 is
a. 0.0252
b. 0.0495
c. 0.0901
d. 0.9010
e. None of the above ____________

(4) Refer to Exhibit 5. What percent of elderly people in this group would we expect to have balances between $180 and $220?
a. 28.81%
b. 45.88%
c. 57.62%
d. 64.23%
e. None of the above ____________

EXHIBIT 6: The starting debt balances for new dentists are normally distributed with a mean of $40,000 and a standard deviation of $5,000.

(5) Refer to Exhibit 6. What is the probability that a randomly selected new dentist will have a starting debt balance of at least $47,500?
a. 0.1534
b. 0.7564
c. 0.0668
d. 0.1053
e. None of the above ___________

(6) Refer to Exhibit 6. What percentage of new dentists will have starting debt balances between $34,000 and $46,000?
a. 38.49%
b. 39.59%
c. 69.76%
d. 76.98%
e. None of the above ____________

EXHIBIT 7: A particular county in Louisiana experienced incidents of West Niles virus at an average rate of 2.6 per month.

(7) Refer to Exhibit 7. What is the probability of at least three persons coming down with West Niles virus during a month?
a. 12.26%
b. 21.76%
c. 26.40%
d. 48.16%
e. None of the above ____________

(8) Refer to Exhibit 7. What is the probability of an incident occurring every 15 days or less (assume a 30-day month)?
a. 27.25%
b. 45.53%
c. 65.67%
d. 72.75%
e. None of the above