If the population proportion is 0.7 . A researcher wants the margin of error to be 0.20 and the level of confidence is 95% . What is the require sample size?

A business has just completed a marketing campaign. They want to determine if their original market share of 50% has increased as a result of the campaign. A survey conducted found 81 out of 150 people had bought the products. Determine whether the company has increased its market share i. Write down the null and alternative hypotheses for this test.ii. The sample proportion value is missing from the output above. What is this value?iii. Explain why we can use the following test static to conduct this test.? =?̂− ?√??⁄?iv. Use either the ?-value or the ? statistic in the output provided to conduct the test. Has the market share of the company increased?v. The marketing team plan to continue to monitor their market share. In a future study, they want to be able to estimate their market share to within +/−5% and with 90% confidence. What size sample is required? Use the sample proportion from part ii.

Use the given confidence interval to find the margin of error and the sample proportion. (0.640,0.670) E= (Type an integer or a decimal.)

What sample size is needed to give a margin of error within ±1.5% in estimating a population proportion with 99% confidence?Round your answer up to the nearest integer.Sample size =

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Use the given confidence interval to find the margin of error and the sample proportion.   ​(0.729​,0.755​)       E=enter your response here ​(Type an integer or a​ decimal.)

A population mean is 13. The sample mean is 12.8, and the sample standard deviation is 2. The sample size is 20. What standard error would you use to conduct a hypothesis test on the mean?

It is desired to estimate the proportion of cannabis users at a university. What is the sample size required to if we wish to have a 95% confidence in the interval and an error of 10%? 385 68 10 97

The high price of medicines is a source of major expense for those seniors in the United States who have to pay for these medicines themselves. A random sample of 1600 seniors who pay for their medicines showed that they spent an average of $4300 last year on medicines with a standard deviation of $500. Make a 90% confidence interval for the corresponding population mean. Round your answers to cents. i to $ i %24

Tina catches a 14-pound bass.  She does not know the population mean or standard deviation.  So she takes a sample of five friends and they say the last bass they caught was 9, 12, 13, 10, and 10 pounds.  Find the t and calculate a 95% (α = .05) confidence interval.