Based on past surveys over several years, a small business believes that 85% of their customers are satisfied with their services. Due to the recent conditions, changes in policy and additional charges, the business decides to select a random sample of 20 recent customers and ask them if they are satisfied with their services. If the number of satisfied customers in the sample is 16 or fewer, the business will conclude that this is an indication of a need for improvement in customer service and they will try to determine ways to provide it. What is the probability that the results of the sample will indicate a need to improve customer service?

Based on past surveys over several years, a small business believes that 85% of their customers are satisfied with their services. Due to the recent conditions, changes in policy and additional charges, the business decides to select a random sample of 20 recent customers and ask them if they are satisfied with their services. If the number of satisfied customers in the sample is 16 or fewer, the business will conclude that this is an indication of a need for improvement in customer service and they will try to determine ways to provide it. What is the probability that the results of the sample will indicate a need to improve customer service?

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The Energy Star rating system is an energy efficiency program run by the U.S. Environmental Protection Agency (EPA)Energy Star certified appliances, such as televisions and refrigerators, are rated in regard to their average energy consumption per year. A certain brand of Energy Star certified refrigerator is stated to have a mean yearly electricity cost of $99. A consumer advocacy organization believes that this claim is wrong, that the energy consumption of this particular refrigerator is different than $99 per year. The group collected a random sample of 16 refrigerators of the model in question and had each lab-tested for electricity consumption. The yearly energy consumption of each is given below. 96.7697.898.67 95.52 97.8 95.896.9299.57 97.64 95.46 98.03 96.42 99.32 98.99 95.2197.12 Using alpha = 0.1 , test the hypothesis that the average yearly electricity consumption of the refrigerator in question is different than $99 per year. Assume that the distribution of all electricity…
A global corporation is currently in the process of expanding its operations, and the only option is to move to another site. The Human Resource Team has conducted a survey to its employees who live far from the site in order to find out if they are willing to stay in dormitories. The survey categorizes its respondents according to gender. In the samples sample of 500 males and 800 females, those who are willing to stay in dormitories are 241 and 168, respectively. Construct a 98% confidence interval for the difference between the two population proportions. Assuming that the HR’s estimated difference between the proportion of genders who are willing to stay in dormitories is 35%, is the team’s estimation accurate?
A substance abuse counselor wants to demonstrate the effect of situational stress on alcohol cravings. He recruits two groups of men who are similar in respect to history of alcohol use and demographic variables. He divides them in to two groups. In one group(n=11), the men are exposed to a stressful situation and then asked to complete a measure rating their alcohol cravings on a scale from 0-10, where 0 representsno cravings and 10 represents intense cravings. In the second group (n=10), the men are exposed to a neutral situation and asked to complete the same measure. What test and graph should I create to find out if a stressful situation result in more intense alcohol cravings than a non-stressful situation?
To the Internal Revenue Service (IRS), the reasonableness of total itemized deductions depends on the taxpayer's adjusted gross income. Large deductions, which include charity and medical deductions, are more reasonable for taxpayers with larg given level of income, the chances of an IRS audit are increased. Data (in thousands of dollars) on adjusted gross income and the average or reasonable amount of itemized deductions follow. Adjusted Gross Income Itemized Deductions ($1,000s) 22 ($1,000) 9.6 27 9.6 32 10.1 48 11.1 65 13.5 85 120 15.7 25.5 (a) Develop a scatter diagram for these data with adjusted gross income as the independent variable. 30 25 20 15 10 5 30 25 20 15 10 5+ 30 25- 20- 15- 10- .. 5- 0 20 40 60 80 100 120 140 Adjusted Gross Income ($1,000s) 0 20 40 60 80 100 120 140 0 Adjusted Gross Income ($1,000s) 20 40 60 80 100 120 140 Adjusted Gross Income ($1,000s) 30 25 20 15 10 5- 0 20 40 60 80 100 Adjusted Gross Income ($1,000s) 120 140 G (b) Use the least squares method to…
Anterior cruciate ligament (ACL) injuries occur most frequently in planting and cutting sports such as basketball, soccer, and volleyball. National collegiate athletic association injury data show that female athletes injure the ACL more frequently than their male counterparts do. A sports medicine professor wants to test this claim. He surveyed 5 universities that had both men's and woman's basketball, soccer, and volleyball and asked them how many grade 3 ACL tears they had during the past 5 seasons. Using the following results, are women at greater risk than men for ACL injuries? (use a standard deviation of 0.01, one tail test). Women- 4,3, 5, 2,4 Men- 2, 0, 1 ,2, 1 What is the difference between a repeated measure study and a matched pairs study?
several years ago, the Gallup Organization conducted a random survey of 1018 adults aged 18 or older living in the United States and asked if you had $1000 to spend. Do you think investing it in the stock market would be a good idea? The Gallup study concluded that 54% of those surveyed said they thought investing in the stock. Market was a good idea. A statician would like to take a random sample of 200 of those 1018 adults and ask them the same question again to see if people change their minds over time. Based on the Gallup survey a statician specs that 54% of their sample will say that investing $1000 in the stock market would be a good idea give or take 2.1% find the chance as a percentage that institutions random sample 51% or more of them would say that investing $1000 in the stock market is a good idea write your answer as a percentage.
Hurricane Andrew swept through southern Florida causing billions of dollars of damage. Because of the severity of the storm and the type of residential construction used in this semitropical area, there was some concern that the average claim size would be greater than the historical average hurricane claim of $25,500. Several insurance companies collaborated in a data gathering experiment. They randomly selected 26 homes and sent adjusters to settle the claims. In the sample of 26 homes, the average claim was $28,000 with a population standard deviation of $6300. Is there sufficient evidence at a 0.01 significance level to support the claim that the home damage is greater than the historical average? Assume the population of insurance claims is approximately normally distributed. Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below. Ho 25,500 Ha H. 25,500
Anterior cruciate ligament (ACL) injuries occur most frequently in planting and cutting sports such as basketball, soccer, and volleyball. National collegiate athletic association injury data show that female athletes injure the ACL more frequently than their male counterparts do. A sports medicine professor wants to test this claim. He surveyed 5 universities that had both men's and woman's basketball, soccer, and volleyball and asked them how many grade 3 ACL tears they had during the past 5 seasons. Using the following results, are women at greater risk than men for ACL injuries? (use a standard deviation of 0.01, one tail test). Women- 4,3, 5, 2,4 Men- 2, 0, 1 ,2, 1 Calcualte the sum of squares of injuries for men.
Camille for her part wants to assess the impact of an awareness campaign aimed at reducing the amount of household food waste. The campaign is taking place in a subset of neighborhoods of Ville de Montréal. Camille’s objective is to compare the average amount of food waste produced in those neighborhoods, with that in neighborhoods not targeted by the campaign. Therefore, she randomly chooses five neighborhoods targeted by the campaign and five neighborhoods where the campaign does not take place. In each of the 10 neighborhoods, she monitors the weekly amount of food waste (kg) for each of a number of households, and calculates amounts on a per household basis; see below. Is the amount of food waste per household in the neighborhoods targeted by the campaign lower, on average, than in those not targeted by the campaign? Use α= 0.05.
In a 2018 Poll 447 out of 486 supported universal background checks for all gun sales in the U.S. In a similar poll from 2015, 276 of 321 interviewed supported universal background checks. Is this significant evidence that the percent of the population that supports universal background checks in the U.S. has decreased during this time?
Suppose you are conducting a study about how the average US worker spends time over the course of a workday. You are interested in how much time workers spend per day on personal calls, emails, and social networking websites, as well as how much time they spend socializing with coworkers versus actually working. The most recent census provides data for the entire population of US workers on variables such as travel time to work, time spent at work, and break time at work. The census, however, does not include data on the variables you are interested in, so you obtain a random sample of 83 full-time workers in the United States and ask about personal calls, emails, and so forth. You are curious about how your sample compares with the census, so you also ask the workers the same questions about work that are asked in the census. Suppose the mean time spent at work per day from the most recent census is 8.32 hours, with a standard deviation of 0.91 hours. Your sample of 83 US workers…
A nationwide job recruiting firm wants to compare the annual incomes for childcare workers in Connecticut and California. Due to recent trends in the childcare industry, the firm suspects that the that the mean annual income of childcare workers in the state of Connecticut is greater than the mean annual income of childcare workers in California. To see if this is true, the firm selected a random sample of 10 childcare workers from Connecticut and an independent random sample of 10 childcare workers from California and asked them to report their mean annual income. The data obtained were as follows. 80°F Partly sunny Annual income in dollars Connecticut 42438, 52287, 46837, 49334, 52848, 52929, 57111, 51860, 44967, 52174 California 50998, 38334, 56804, 50919, 49446, 41141, 45717, 43963, 55156, 47295 LL D 144Hz Send data to calculator V The population standard deviations for the annual incomes of childcare workers in Connecticut and in California are estimated as 6300 and 6100,…