Question

1-Karen wants to advertise how many chocolate chips are in each Big Chip cookie at her bakery. She randomly selects a sample of 55 cookies and finds that the number of chocolate chips per cookie in the sample has a mean of 9.4 and a standard deviation of 1.1. What is the 95% confidence interval for the number of chocolate chips per cookie for Big Chip cookies? Enter your answers accurate to one decimal place (because the sample statistics are reported accurate to one decimal place).

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2- You measure 37 textbooks' weights, and find they have a mean weight of 48 ounces. Assume the population standard deviation is 9.6 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight.

Give your answers as decimals, to two places

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3-

The effectiveness of a blood-pressure drug is being investigated. An experimenter finds that, on average, the reduction in systolic blood pressure is 56.8 for a sample of size 855 and standard deviation 13.9.

Estimate how much the drug will lower a typical patient's systolic blood pressure (using a 80% confidence level).

Enter your answer accurate to one decimal place (because the sample statistics are reported accurate to one decimal place).

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4-At a traffic stop on a Saturday night 21% of 87 drivers were intoxicated. What is the 95% confidence interval for the population proportion of drunk drivers?

Give your answers as decimals, to two places.

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Answer 1