There are 3 boys and 2 girls at a party. Three party-goers are selected at random to go on a root-beer run. Let W denote the number of girls in the group of three that go on the root-beer run. Compute the expected number of girls who go on the root-beer run, E[W].

There are 3 boys and 2 girls at a party. Three party-goers are selected at random to go on a root-beer run. Let W denote the number of girls in the group of three that go on the root-beer run. Compute the expected number of girls who go on the root-beer run, E[W].

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

See similar textbooks

Similar questions

Ten kids line up in a random order. There are three boys and seven girls in the group. Let X be a random variable denoting the number of boys in the front half of the line. Give the pdf of X:
2. Let X be the mean of a random sample of n = 25 from N(30, 9). Find the probability that the sample mean is between 29.8 and 30.6.
Q1. a) In a group of 80 students, 50 have a laptop (A), 30 have a tablet (B) and 3 have both a laptop and a tablet. i) Draw a Venn diagram to represent this information. A 47 3 27 B 3 ii) Find the probability that a student either only has a tablet or does not have a laptop or both, using the equation P(A' U B) = P(A') + P(B) – P(A' ŉ B).
The table below shows the soft drink preferences of people in three age groups. If one of the 255 subjects is randomly selected, find the probability that the person drinks root beer or cola given that they are under 21 years of age
A particular lake is known to be one of the best places to catch a certain type of fish. In this table, x = number of fish caught in a 6-hour period. The percentage data are the percentages of fishermen who caught x fish in a 6-hour period while fishing from shore. A) Find the probability that a fisherman selected at random fishing from shore catches one or more fish in a 6-hour period. B) Find the probability that a fisherman selected at random fishing from shore catches two or more fish in a 6-hour period. C) Compute ?, the expected value of the number of fish caught per fisherman in a 6-hour period (round "at least 4" to 4). D) Compute ?, the standard deviation of the number of fish caught per fisherman in a 6-hour period (round "at least 4" to 4).
Of the cartons produced by a company, 3% have a puncture, 6% have a smashed corner, and 0.5% have both a puncture and a smashed corner. Find the probability that a randomly selected carton has a puncture or a smashed corner. The probability that a randomly selected carton has a puncture or a smashed corner %. Type an integer or a decimal. Do not round.) Time Remaining: 01:02:00 Next:
Use the data in the following table, which lists drive-thru order accuracy at popular fast food chains. Assume that orders are randomly selected from those included in the table. Drive-thru Restaurant с 245 35 B 280 60 A Order Accurate 313 Order Not Accurate 38 If two orders are selected, find the probability that they are both accurate. Complete parts (a) and (b) below. The probability is. The events (Do not round until the final answe a. Assume that the selections are made with replacement. Are the events independent? The probability is. The events independent. (Do not round until the final answer. Round to four decimal places as needed.) b. Assume that the selections are made without replacement. Are the events independent? independent. D 129 10 are not are cimal places as needed.) ...
9(D)
Find the number of ways in which one A, three B’s, two C’s, and one F can be distributed among seven stu-dents taking a course in statistics.
3. Consider the joint PDF fx. (x,y) given in the following. (2+y) if 0
Teachers want to know which night each week their students are doing most of their homework. Most teachers think that students do homework equally throughout the week. Suppose a random sample of students were collected which shows that the Number of students doing their homework on SUN where 16 Number of students doing their homework on MON where 18 Number of students doing their homework on TUE where 12 Number of students doing their homework on WED where 18 Number of students doing their homework on THR where 8 Number of students doing their homework on FRI where 4 Number of students doing their homework on SAT where 3 What is the Test Statistics to test the Hull Hypothesis that students were doing their homework with equal frequencies (that is, they fit a uniform distribution) against the alternative Hypothesis that students prefer doing their homework on a particular day (that is, they do not fit a uniform distribution)?