Calculating Probabilities Based on a Saint Index survey, assume that when adults are asked to identify the most unpopular projects for their hometown, 54% include WalMart among their choices. Suppose we want to find the probability that when five adults are randomly selected, exactly two of them include WalMart. What is wrong with using the multiplication rule to find the probability of getting two adults who include WalMart followed by three people who do not include WalMart, as in this calculation: (0.54)(0.54)(0.46)(0.46)(0.46)?
Read moreTable of Contents
Textbook Solutions for Elementary Statistics
Question
Online Banking Based on data from a USA Today Snapshot, 72% of adults have security concerns about online banking. Find the probability that among 30 randomly selected adults, exactly 20 have security concerns. Among 30 random adults, is 20 an unusually low number for those who have security concerns?
Solution
The first step in solving 5-3 problem number 36 trying to solve the problem we have to refer to the textbook question: Online Banking Based on data from a USA Today Snapshot, 72% of adults have security concerns about online banking. Find the probability that among 30 randomly selected adults, exactly 20 have security concerns. Among 30 random adults, is 20 an unusually low number for those who have security concerns?
From the textbook chapter Binomial Probability Distributions you will find a few key concepts needed to solve this.
Visible to paid subscribers only
Step 3 of 7)Visible to paid subscribers only
full solution