Probability unit Exam Questions and Answers.

Probability unit Exam Questions and Answers expected value - Correct Answers: value of an experiment that is the long-term average value of repetitions of an experiment. It is obtained by summing the products of the values associated with each possible outcome by its probability fundamental counting principle (permutations) - Correct Answers: if Act 1 can be performed in m ways, and Act 2 can be performed in n ways, no matter how Act 1 turns out, then the sequence Act 1 -> Act 2 can be performed in (m)(n) ways ordered selections (permutations) - Correct Answers: nPr = n(n-1)(n-2) combination - Correct Answers: is a selection in which order does NOT matter. A common notation nCr is used for the number of selections of size r from n objects nCr = (n(n-1)(n-2)) / (r(r-1)) probabilistic situation - Correct Answers: a situation in which we are interested in the fraction of the number of repetitions of a particular chance process that produces a particular result when repeated under identical circumstances a large number of times experiment - Correct Answers: a chance process undertaken a large number of times with results outcome - Correct Answers: a particular result of an experiment event - Correct Answers: an outcome or a set of outcomes of a designated type probability of an event - Correct Answers: the fraction of the times the event will occur when some process is repeated a large number of times-- fractions, decimals, and percentages are all used to express probabilities theoretical probability - Correct Answers: a probability that can be arrived at by the knowledge based on a theory of what is likely to occur in a situation, such as when a fair coin is tossed experimental (or empirical probability) - Correct Answers: an application of the adage "What has happened in the past will happen in the future." - determined by undertaking a process a large number of times and noting the fraction of times the particular event occurs sample space - Correct Answers: all the outcoes together - P(a) = number of times A happens / total number of outcomes in the sample space P(rolling a 6) - 1/6 odds - Correct Answers: term used to compare an event with the corresponding non-event "odds" of drawing an ace from a regular deck of cars is 4 to 48 or 1 to 12." simulation - Correct Answers: randomly selected numbers to find a probability in this manner randomly selected number or object - Correct Answers: from a set of numbers or objects is one that has a chance of being selected that is equal to that of any other number or object in the set multistep experiment - Correct Answers: carefully list all the ways that the experiment could turn out (I.E., list the complete sample space and then see which outcomes favor the event.) addition rule for probability - Correct Answers: P(A or B) = P(A) + P(B) - P(A and B) disjoint - Correct Answers: two events are mutually exclusive when it is impossible for them to happen simultaneously independent - Correct Answers: when the occurrence of one event does not change the probability of the other event. The probability of both events happening simultaneously is the product of the two probabilities. For events A and B P(A and B) = P(A) x P(B) conditional probability - Correct Answers: the probability of an event that is contingent of another event's occurrence contingency rule - Correct Answers: organizes data in a manner that allows us to determine the conditional probability of an event conditional probabilities - Correct Answers: P(A|B) = P(A and B) / P(B) Yes. a zero probability means that none of the outcomes are examples of the event -- e.g., getting a 7 on a toss of a die - Correct Answers: is it possible for the probability of some event to be 0? explain Yes. A probability of one means that all of the outcomes are examples of the event -- e.g., getting 12 or fewer on a toss of two dice. - Correct Answers: is it possible for the probability of some event to be 1? Explain. No. Probability can only be measured between 0 and 1 - Correct Answers: is it possible for the probability of some event to be 1.5? explain. rolling 12 or fewer on two dice - Correct Answers: situation in which probability of a certain-to-happen event is 1 rolling a 13 on two dice - Correct Answers: situation in which probability of a certain-to-happen event is 0 experimental - Correct Answers: experimental or theoretical "Drawing a red M&M from a package of M&Ms" Theoretical out of the 6 outcomes, one outcome favors getting a 2, so 1/6 - Correct Answers: experimental or theoretical "getting a 2 on the throw of one die" theoretical, out of the 52 outcomes, 13 outcomes favor selecting a heart, so 13/52 - Correct Answers: experimental or theoretical selecting a heart from a regular deck of cards (m / m + r)--> m:r 3:10 - Correct Answers: what probability statement says the same thing as "The odds for the Mammoths winning are 3 to 10? the odds for making a field goal are 2 to 1 - Correct Answers: restate in terms of odds: The probability of making a field goal is 2/3 the odds for drawing a red ball from the bag is 7 to 5 - Correct Answers: restate in terms of odds: The probability of drawing a red ball from the bag is 7/12 the odd against getting a winning card is 7 to 23. - Correct Answers: the probability of not getting a winning card is 7/30 NO INTERSECTION "mutually exclusive" - Correct Answers: disjoint a AND b = (A)(B) - Correct Answers: independent