Exam 8: Random Sampling and Probability

A certain university maintains a colony of male mice for research purposes. The ages of the mice are normally distributed with a mean of 60 days and a standard deviation of 5.2. Assume you randomly sample one mouse from the colony. The probability his age will be greater than 68 is _________.

If A and B are mutually exclusive and exhaustive, then p ( A and B ) = _________.

In a box there are 10 slips of paper and each slip of paper has a number from 0 to 9 on it so that all the numbers appear once and only once.

Assume you are sampling one score from a rectangular distribution of population scores having a mean = 40 and a standard deviation = 15. You want to determine the probability of getting a score ?5= 48. You compute the z transformation of 48 and look up the area corresponding to the z score in Table A (column C) of your textbook. You conclude that this area gives the desired probability. Is this conclusion correct? Discuss.

Let's assume you are having a party and have stocked your refrigerator with beverages. You have 12 bottles of Coors beer, 24 bottles of Rainier beer, 24 bottles of Schlitz light beer, 12 bottles of Hamms beer, 2 bottles of Heineken dark beer and 6 bottles of Pepsi soda. You go to the refrigerator to get beverages for your friends. In answering the following question assume you are randomly sampling without replacement. What is the probability the first beverage you get is a beer?

Define a posteriori probability .

A "hungry" undergraduate student was looking for a way of making some extra money. The student turned to a life of vice - gambling. To be a good gambler, he needed to know the probability of certain events. Help him out by answering the following question A royal flush in poker is when you end up with the ace, king, queen, jack, and 10 of the same suit. It's the most rare event in poker. If you are playing with a well- shuffled, legitimate deck of 52 cards, what is the probability that if you are dealt 5 cards, you will have a royal flush? Assume randomness.

There is no division rule for probability.

An a posteriori approach to probability is never used because it is only an approximation of the true probability.

A priori and a posteriori probability have the same meaning.

If events are mutually exclusive they cannot be _________.

If µ = 35.2 and s = 10, then p ( X ) for X ≤ 39 equals _________. Assume random sampling.

Let's assume you are having a party and have stocked your refrigerator with beverages. You have 12 bottles of Coors beer, 24 bottles of Rainier beer, 24 bottles of Schlitz light beer, 12 bottles of Hamms beer, 2 bottles of Heineken dark beer and 6 bottles of Pepsi soda. You go to the refrigerator to get beverages for your friends. In answering the following question assume you are randomly sampling without replacement. What is the probability the first four bottles you select will be a Coors, a Schlitz, a Rainier, and a Coors in that order?

In a class of 30 children who cannot swim, the instructor randomly selects a child and then teaches the child to swim.

A "hungry" undergraduate student was looking for a way of making some extra money. The student turned to a life of vice - gambling. To be a good gambler, he needed to know the probability of certain events. Help him out by answering the following question. The probability of drawing a face card (king, queen or jack) of any suit from a deck of 52 ordinary playing cards in one draw is _________.

Sampling without replacement is usually used in choosing subjects for an independent groups design experiment.

If p ( A and B ) = p ( A ) p ( B | A ) ≠ p ( A ) p ( B ), then A and B are _________.

Two events are mutually exclusive if _________.

Two events are independent if the occurrence of one has no effect on the probability of occurrence of the other.

Assume you are rolling two fair dice once . The probability of obtaining a sum of 2 or 12 equals _________.