Which of the following statements is consistent with the quantity theory of money?

• Monetary policy should be used in the short run to try to steer the economy.

• The money supply should be increased by a percentage to allow for changes in productivity and growth, but that percentage cannot be determined.

• Expansionary monetary policy is the only way to prevent a mild recession from developing into a serious recession or depression.

• A prescribed monetary policy should be followed regardless of what's happening in the economy.

Find the margin of error and 95% confidence interval for the following surveys. Round all answers to 2 decimal places.

a) A survey of 500 people finds that 67% plan to vote for Smith for governor. Margin of Error (as a percentage): answer  _____ Confidence Interval: answer _____ % to answer ____ %

b) A survey of 1500 people finds that 44% support stricter penalties for child abuse.

Margin of Error (as a percentage): answer ____ Confidence Interval: answer _____ % to answer _____ %

A population of women’s weights is approximately normally distributed with a mean of 140 lb and a standard deviation of 20 lb.

1. What percentage of women weigh between 120 and 160 lb?

2. If samples of size 16 are drawn from the population of women’s weights, what percentage of the sample means lie between 120 and 160 lb?

3. What is the probability that a sample mean from a sample size 16 lies above 145 lb?

The Acme Company manufactures widgets. The distribution of widget weights is approximately normal with a mean of 53 ounces and a standard deviation of 10 ounces. Use the Empirical Rule to answer the questions below. Sketch the distribution in order to answer these questions. (a) 99.7% of the widget weights lie between and (b) What percentage of the widget weights lie between 43 and 83 ounces? % (c) What percentage of the widget weights lie below 73 ? %

The historical returns on a balanced portfolio have had an average return of 12% and a standard deviation of 20%. Assume that returns on this portfolio follow a normal distribution. [Use Excel commands instead of the z table.]

a. What percentage of returns were greater than 52%? (Round your answer to 2 decimal places.)

b. What percentage of returns were below −48%? (Round your answer to 2 decimal places.)

The Acme Company manufactures widgets. The distribution of widget weights is bell-shaped. The widget weights have a mean of 63 ounces and a standard deviation of 5 ounces. Use the Standard Deviation Rule, also known as the Empirical Rule.

a) 99.7% of the widget weights lie between _____ and _____

b) What percentage of the widget weights lie between 53 and 78 ounces? %

c) What percentage of the widget weights lie below 68 ?

Problems 16-18: Lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days.(Use the z-table). What percentage of pregnancies last less than 250 days?

What percentage of pregnancies last more than 280 days?

If 60 pregnant women were randomly selected, how likely is it that their mean pregnancy length is greater than 275 days? Your answer:

Assume that military aircraft use ejection seats designed for men weighing between

149.6149.6

lb and

212212

lb. If​ women's weights are normally distributed with a mean of

177.2177.2

lb and a standard deviation of

48.748.7

​lb, what percentage of women have weights that are within those​ limits? Are many women excluded with those​ specifications?

The percentage of women that have weights between those limits is

nothing​%.

​(Round to two decimal places as​ needed.)

In a study of the accuracy of fast food​ drive-through orders, Restaurant A had 315 accurate orders and 63 that were not accurate. a.) Construct a 95​% confidence interval estimate of the percentage of orders that are not accurate. b.) Compare the results from part​(a) to this 90​% confidence interval for the percentage of orders that are not accurate at Restaurant​ B: 0.144< p < 0.226. What do you​ conclude?

a) Construct a 90% confidence interval. Express the percentages in decimal form.

10. State which is the most appropriate: z or t or neither. Give the critical value when you can.

            95% confidence; ; ; population has an outlier

11. We want to know if the percentage of last-born children who are the most assertive has changed from the 43% estimate from a study in 2017. How many families should be selected to produce an estimate that is within 1.2% of the population percentage with 98% confidence?