9. Find a value of the standard normal random variable z, called z0 , such that P(z z0 ) = 0.70. (a) -.98 (b) -.81 (c) -.47 (d) -.53 10. The weight of corn chips dispensed into a 24-ounce bag by the dispensing machine has been identified as possessing a normal distribution with a mean of 24.5 ounces and a standard deviation of 0.2 ounce. What proportion of the 24-ounce bags contain more than the advertised 24 ounces of chips? (a) .0062 (b) .9938 (c) .4938 (d) .5062 11. In a recent test, the mean SAT score of all students was 1020. Laura is planning to take this test soon. Suppose the SAT scores of all students who take this test with Laura will have a normal distribution with a mean of 1020 and a standard deviation of 153. What should Laura's score be on this test so that only 10% of all examinees score higher than she does? (a) 1173 (b) 867 (c) 1216 (d) 1326 12. In skewed-right distributions, what is the relationship of the mean, median, and mode? (a) Mean > Median > Mode (b) Median > Mean > Mode (c) Mode > Median > Mean (d) Mode > Mean > Median 13. How are and related? (a) is the sample mean that we often use to estimate , the population mean; (b) and are both measures of central tendency for a data set; (c) is the population mean that we often use to estimate , the sample mean; (d) is the sample mean that we often use to estimate , the population mean; 14. The distribution of the amount of money spent on book purchases for a semester by MUN students has a mean of $280 and a standard deviation of $40. If the distribution is mound shaped and symmetric, what proportion of students will spend approximately between $160 and $320 this semester? (a) 0.9500 (b) 0.9750 (c) 0.8150 (d) 0.8400 15. If events A and B are independent and P(A) = 0.6 and P(B) = 0.4, which of the following is correct? (a) P(A|B) = 0.50 (b) P(A B) = 0.76 (c) P(A B) = 1.00 (d) P(A B) = 0.24 18. What is the relationship between the events B and Bc? (a) P(B| Bc) = 1 (b) P(B| Bc) = 0 (c) P(B Bc) = 0 (d) P(B Bc ) = 1 19. Given two events F and G such that P(F) = 0.40, P(G) = 0.25 and P(F|G) = 0.75. Then the value of the probability P(G F) is: (a) 0.3375 (b) 0.1875 (c) 0.6500 (d) 0.4625 20. What is the value of z0 for the standard normal random variable Z such that P{z0 Z