Question 15 < 0/1 pt 3 2 Details You work for a marketing firm that has a large client in the automobile industry. You have been asked to estimate the proportion of households in Chicago that have two or more vehicles. You have been assigned to gather a random sample that could be used to estimate this proportion to within a 0.025 margin of error at a 99% level of confidence. a) With no prior research, what sample size should you gather in order to obtain a 0.025 margin of error? Round your answer up to the nearest whole number. n = households b) Your firm has decided that your plan is too expensive, and they wish to reduce the sample size required. You conduct a small preliminary sample, and you obtain a sample proportion of p=0.21. Using this new information. what sample size should you gather in order to obtain a 0.025 margin of error? Round your answer up to the nearest whole number. n = households Submit Question

A student wishes to determine the average life-span of a household light bulb. She randomly collects 15 light bulbs. The issue that may arise from her survey is…    The bias will be high. The accuracy will be low. The precision will be low. The standard error will be too low.

An article claims that 70% of adults over 50 take vitamin supplements. To test this claim, you take a sample and do your math. Based on your results, you end up rejecting the claim. Later it turns out that the claim was in fact correct. What type of error did you make, if any? No error was made. A type II error A type I error

a) Work this problem manually (by hand) using the procedures and formulas for ANOVA to check if the Population Means for flying time before major maintenance is required are the same for the three types of aircraft.   To help you, Sample Means and Sample Variances have been calculated below for you:                      Airbus                Boeing737            Boeing 787                        6.4                           8.7                          9.9                        7.8                           7.4                          12.8                        5.3                            9.4                         12.1                       7.4                            10.1                        10.8                       8.4                            9.2                          11.3                       7.3                            9.8                          11.5 __________________________________________________________________ Sample Mean         7.1…

In a simple random sample of 1200 young​ people, 86​% had earned a high school diploma. What is the standard error for this estimate of the percentage of all young people who earned a high school​ diploma?

A publisher reports that 69 % of their readers own a particular make of car. A marketing executive wants to test the claim that the percentage is actually under the reported percentage. A random sample of 200 found that 60% of the readers owned a particular make of car. Is there sufficient evidence at the 0.10 level to support the executive's claim? Step 5 of 7: Identify the value of the level of significance.

Suppose a researcher wants to estimate the population proportion of defective light bulbs. He took a random sample of 800 light bulbs and 40 of them found out to be defective.  Suppose the researcher claims that the defective proportion of light bulb is less than 7%. Suppose he wants to test this claim at 5% significance level.   Calculate the test statistics. (Round your answer to two decimal places )