A limousine company is concerned with increasing costs of maintaining their fleet of 150 cars. After testing, the company found that the emissions systems of 9out of the 20 cars they tested failed to meet pollution control guidelines. They had forecasted costs assuming that a total of 54 cars would need updating to meet the latest guidelines. Is this strong evidence that more than 36% of the fleet might be out of compliance? Test an appropriate hypothesis and state your conclusion. Be sure the appropriate assumptions and conditions are satisfied before you proceed.

A limousine company is concerned with increasing costs of maintaining their fleet of 150 cars. After testing, the company found that the emissions systems of 9out of the 20 cars they tested failed to meet pollution control guidelines. They had forecasted costs assuming that a total of 54 cars would need updating to meet the latest guidelines. Is this strong evidence that more than 36% of the fleet might be out of compliance? Test an appropriate hypothesis and state your conclusion. Be sure the appropriate assumptions and conditions are satisfied before you proceed.

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter4: Equations Of Linear Functions

Section: Chapter Questions

Problem 8SGR

See similar textbooks

Similar questions

In the nation of Gondor, the EPA requires that half the new cars sold will meet a certain particulate emission standard a year later. A sample of 64 one-year-old cars revealed that only 20 met the particulate emission standard. What is the test statistic to see whether the proportion is below the requirement?
As a result of complaints from customers about delivery times, the manager at a pizza delivery service is ready to undertake a study to determine whether the average delivery time differs from the status quo of 30 minutes. State the null and alternative hypotheses.
What would you conclude based on an α=0.05 level? We reject the null hypothesis and do not accept the alternative hypothesis since there is sufficient evidence that the proportion of all vehicles that meet or exceed current fuel economy standards is greater than 90% due to the p-value being greater than the α level. Explain the results of your hypothesis test. What does the p-value signify? Would you say the observed outcome was unusual? If so, how unusual was the outcome?
(1) Conduct a hypothesis test, at the 5% level of significance, to determine whether ? is significant (2) What would be the growth of the plant if 4g of fertilizer and 7g of ater was given to it daily? (3) Carry out an F -test at the 1% significance level to determine whether the model is significant
Historically, the proportion of students entering a university who finished in 4 years or less was 65%. To test whether this proportion has decreased, 150 students were examined and 58% had finished in 4 years or less. At the 5% level of significance, does it appear the proportion has decreased from its historical level? To determine whether the proportion of students who finish in 4 year or less has statistically significantly decreased, what is the null and alternative hypothesis?
Since its removal from the banned substances list in 2004 by the World Anti-Doping Agency,caffeine has been used by athletes with the expectancy that it enhances their workout andperformance. However, few studies look at the role caffeine plays in sedentary females.Researchers at the University of Western Australia conducted a test in which they determined therate of energy expenditure (kilojoules) on 10 healthy, sedentary females who were nonregularcaffeine users. Each female was randomly assigned either a placebo or caffeine pill (6mg/kg) 60minutes prior to exercise. The subject rode an exercise bike for 15 minutes at 65% of theirmaximum heart rate, and the energy expenditure was measured. The process was repeated on aseparate day for the remaining treatment. The mean difference in energy expenditure (caffeine –placebo) was 18kJ with a standard deviation of 19kJ. If we assume that the differences follow anormal distribution can it be concluded that that caffeine appears to increase…
A poll of 700 frequent and occasional fliers found that 450 respondents favored a ban on cellphones in flight, even if technology permits it. At α = .05, can we conclude that morethan half the sampled population supports a ban?
To combat antibiotic resistance, the Quality Improvement Consortium recommends a throat swab to confirm strep throat before a physician prescribes antibiotics to children under age 5. Nationally, 40 percent of children under 5 who received antibiotics did not have a throat swab. The Colorado Department of Health took a random sample of 60 children under the age of 5 who received antibiotics for throat infections and found that 18 did not have a throat swab. At α = .05, is this a statistically significant reduction over last year’s national rate of 40 percent? (a-1) Calculate the critical value. (A negative value should be indicated by a minus sign. Round your answer to 3 decimal places.) Critical value _____ (a-2) Calculate the test statistic. (A negative value should be indicated by a minus sign. Round your answer to 2 decimal places.) Test statistic _____
The worker on examining his 20 rainfall sample points concluded that it is more than likely to rain on this May 1st. Describe two or three statistical steps he took to arrive at this conclusion.
To combat antibiotic resistance, the Quality Improvement Consortium recommends a throat swab to confirm strep throat before a physician prescribes antibiotics to children under age 5. Nationally, 40 percent of children under 5 who received antibiotics did not have a throat swab. The Colorado Department of Health took a random sample of 100 children under the age of 5 who received antibiotics for throat infections and found that 30 did not have a throat swab. At α = .05, is this a statistically significant reduction over last year’s national rate of 40 percent? (a-1) Choose the correct null and alternative hypotheses. H0: π ≥ .40 vs. H1: π < .40 H0: π ≤ .40 vs. H1: π > .40 H0: π = .40 vs. H1: π ≠ .40 (a-2) Calculate the critical value. (A negative value should be indicated by a minus sign. Round your answer to 3 decimal places.) Critical value (a-3) Calculate the test statistic. (A negative value should be indicated by a minus sign. Round your…
A major credit card company is interested in the proportion of individuals who use a competitor’s credit card. Their null hypothesis is H0: p=0.65H0: p=0.65, and based on a sample they find a sample proportion of 0.70 and a pp-value of 0.053. Is there convincing statistical evidence at the 0.05 level of significance that the true proportion of individuals who use the competitor’s card is actually greater than 0.65 ?
You want to conduct a test to determine whether there are significant differences in the mean impurity levels for polymers produced with three different catalysts. Which statistical test is appropriate for this scenario? Select one: a. paired t test b. one-sample t test c. one-way ANOVA d. two-sample t test