Tian

Your small library of books consists of 6 novels, 7 mathematics books, and 1 biology book. Calculate the number of ways to arrange them on a bookshelf for each of these situations. a) The books can be arranged in any order? b The novels must be together b...

From past experience it is felt that the random variable, X, the age of a mother at the birth of her first child, is normally distributed with a mean of 21.3 and a variance of 16. Find the probability that a randomly selected mother: (a) has her first chi...

A business firm considers the number of years of formal education, X, a prime factor in screening applicants for employment in its plant. Assume from past experience that X ~ N (10.6, 2.5), where 10.6 is the mean and 2.5 is the standard deviation. (a) If...

1. Past experience indicates that the variance, ¦Ò2x, of the scores, X, obtained on the verbal portion of a test is 5,625. Similarly, the variance ¦Ò2y, of the scores, Y, on the mathematical portion is 2,500. (a) A random sample of size n = 64 yields a sa...

2. A sociologist conducted a study of divorce patterns in a Midwestern city. In the study, 200 divorced people were selected at random, and X, the number of years married before divorce, was measured. From this sample, it was found that the sample mean wa...

3. In studying the efficiency of the federal court system, we look at the random variable, X, the amount of time elapsing between the filing of a charge and the trial date. A random sample of n = 86 cases yields a sample mean of 11.4 months, with sample v...

A certain lottery has 29 numbers. In how many different ways can 6 of the numbers be selected? Assume that order of selection is not important

475,020

Three thousand