Author:
Christine Farr

Event A occurs with probability 0.2. Event B occurs with probability 0.9. Events A and BA. are disjoint.B. are reciprocating.C. cannot be disjoint.D. cannot be independent.2. Choose an American adult at random. The probability that you choose a woman is 0.54. The probability that the person you choose has never married is 0.24. The probability that you choose a woman who has never married is 0.11. The probability that the person you choose is either a woman or never married (or both) is therefore aboutA. 0.67.B. 0.78.C. 0.13.Many random number generators allow users to specify the range of the random numbers to be produced. Suppose that you specify that the random number Y can take any value between 0 and 2. Then the density curve of the outcomes has constant height between 0 and 2, and height 0 elsewhere.3. Is the random variable Y discrete or continuous? Why?A. Continuous, because the length of the interval is finite.B. Discrete, because we do not know the number that will be chosen.C. Discrete, because the sample space {0, 2} is finite.D. Continuous, because there is an infinite number of values in the interval.4. What is the height of the density curve between 0 and 2? Draw a graph of the density curve.5. Use your graph of the density curve and the fact that probability is area under the curve to find P(Y ≤ 1).Spell-checking software catches "nonword errors" that result in a string of letters that is not a word, as when "the" is typed as "teh."When undergraduates are asked to type a 250-word essay (without spell-checking), the number X of nonword errors has the following distribution:

Tutorial