All Subjects

ACT

Algebra

Biology

Calculus 1 / AB

Calculus 2 / BC

Calculus 3

Chemistry 101

Chemistry 102

Geometry

Intro Stats / AP Statistics

Macroeconomics

Microeconomics

Organic Chemistry

Physics 101 Mechanics

Physics 102 Electricity and Magnetism

Physics 103

Prealgebra

Precalculus

Psychology

Adrianna A.

Intro Stats / AP Statistics

6Â hours ago

The table below lists body temperatures obtained from randomly selected subjects (based on Data Set 3 â€śBody Temperaturesâ€ť in Appendix B). Using a 0.05 significance level, test for an interaction between gender and smoking, test for an effect from gender, and test for an effect from smoking. What do you conclude?

Patrick F.

Intro Stats / AP Statistics

13Â hours ago

The average full-time faculty member in a postsecondary degree-granting institution works an average of 53 hours per week. a. If we assume the standard deviation is 2.8 hours, what percentage of faculty members work more than 58.6 hours a week? b. If we assume a bell-shaped distribution, what percentage of faculty members work more than 58.6 hours a week?

Lisa C.

Intro Stats / AP Statistics

13Â hours ago

The average farm in the United States in 2014 contained 504 acres. The standard deviation is 55.7 acres. Use Chebyshevâ€™s theorem to find the minimum percentage of data values that will fall in the range of 364.75 and 643.25 acres.

Hannah D.

Intro Stats / AP Statistics

13Â hours ago

The average college student produces 640 pounds of solid waste each year. If the standard deviation is approximately 85 pounds, within what weight limits will at least 88.89% of all studentsâ€™ garbage lie?

Alex T.

Intro Stats / AP Statistics

13Â hours ago

The average age of the accountants at Three Rivers Corp. is 26 years, with a standard deviation of 6 years; the average salary of the accountants is $\$ 31,000,$ with a standard deviation of $\$ 4000 .$ Compare the variations of age and income.

Elizabeth G.

Intro Stats / AP Statistics

13Â hours ago

Starting teachersâ€™ salaries (in equivalent U.S. dollars) for upper secondary education in selected countries are listed. Find the range, variance, and standard deviation for the data. Which set of data is more variable? (The U.S. average starting salary at this time was $\$ 29,641.) $$\begin{array}{llll}{\text { Sweden }} & {\$ 48,704} & {\text { Korea }} & {\$ 26,852} \\ {\text { Germany }} & {41,441} & {\text { Japan }} & {23,493} \\ {\text { Spain }} & {32,679} & {\text { India }} & {18,247} \\ {\text { Finland }} & {32,136} & {\text { Malaysia }} & {13,647} \\ {\text { Denmark }} & {30,384} & {\text { Philippines }} & {9,857} \\ {\text { Netherlands }} & {29,326} & {\text { Thailand }} & {5,862} \\ {\text { Scotland }} & {27,789} & {}\end{array}$$

Patrick G.

Intro Stats / AP Statistics

13Â hours ago

You take a quiz with 6 multiple choice questions. After you studied, you estimated that you would have about an 80% chance of getting any individual question right. What are your chances of getting them all right? Use at least 20 trials.

Amanda W.

Intro Stats / AP Statistics

13Â hours ago

In the chapterâ€™s example, 20% of the cereal boxes contained a picture of LeBron James, 30% Danica Patrick, and the rest Serena Williams. Suppose you buy five boxes of cereal. Estimate the probability that you end up with a complete set of the pictures. Your simulation should have at least 20 runs.

Erica S.

Intro Stats / AP Statistics

13Â hours ago

When drawing five cards randomly from a deck, which is more likely, two pairs or three of a kind? A pair is exactly two of the same denomination. Three of a kind is exactly 3 of the same denomination. (Donâ€™t count three 8â€™s as a pairâ€”thatâ€™s 3 of a kind. And donâ€™t count 4 of the same kind as two pairâ€”thatâ€™s 4 of a kind, a very special hand.) How could you simulate 5-card hands? Be careful; once youâ€™ve picked the 8 of spades, you canâ€™t get it again in that hand. a) Describe how you will simulate a component. b) Describe how you will simulate a trial. c) Describe the response variable.

Stephanie G.

Intro Stats / AP Statistics

13Â hours ago

Youâ€™re pretty sure that your candidate for class president has about 55% of the votes in the entire school. But youâ€™re worried that only 100 students will show up to vote. How often will the underdog (the one with 45% support) win? To find out, you set up a simulation. a) Describe how you will simulate a component. b) Describe how you will simulate a trial. c) Describe the response variable.

Bonnie P.

Intro Stats / AP Statistics

13Â hours ago

Many kinds of games people play rely on randomness. Cite three different methods commonly used in the attempt to achieve this randomness, and discuss the effectiveness of each.

Chelsea W.

Intro Stats / AP Statistics

13Â hours ago

A tire manufacturer believes that the treadlife of its snow tires can be described by a Normal model with a mean of 32,000 miles and standard deviation of 2500 miles. a) If you buy a set of these tires, would it be reasonable for you to hope theyâ€™ll last 40,000 miles? Explain. b) Approximately what fraction of these tires can be expected to last less than 30,000 miles? c) Approximately what fraction of these tires can be expected to last between 30,000 and 35,000 miles? d) Estimate the IQR of the treadlives. e) In planning a marketing strategy, a local tire dealer wants to offer a refund to any customer whose tires fail to last a certain number of miles. However, the dealer does not want to take too big a risk. If the dealer is willing to give refunds to no more than 1 of every 25 customers, for what mileage can he guarantee these tires to last?

Patrick T.

Intro Stats / AP Statistics

13Â hours ago

This histogram displays NFL data from the 2010 football season reporting the number of yards gained by each of the leagueâ€™s 191 wide receivers: The mean is 397.15 yards, with a standard deviation of 362.4 yards. a) According to the Normal model, what percent of receivers would you expect to gain more yards than 2 standard deviations above the mean number of yards? b) For these data, what does that mean? c) Explain the problem in using a Normal model here.

Lisa M.

Intro Stats / AP Statistics

13Â hours ago

Medical researchers followed 1435 middle-aged men for a period of 5 years, measuring the amount of Baldness present (none = 1, little = 2, some = 3, much = 4, extreme = 5) and presence of Heart Disease (No = 0, Yes = 1). They found a correlation of 0.089 between the two variables. Comment on their conclusion that this shows that baldness is not a possible cause of heart disease.

Janet R.

Intro Stats / AP Statistics

13Â hours ago

Mina is waiting in line at the Department of Motor Vehicles (DMV). Her wait time of 32 minutes is the 85th percentile of wait times. Is that good or bad? Write a sentence interpreting the 85th percentile in the context of this situation.

Educator P.

Intro Stats / AP Statistics

13Â hours ago

On an exam, would it be more desirable to earn a grade with a high or low percentile? Explain.

Cindy B.

Intro Stats / AP Statistics

13Â hours ago

About what percent of the cockroaches have weights between 76 and 84 grams? $\begin{array}{ll}{\text { (a) } 99.7 \%} & {\text { (c) } 68 \%} \\ {\text { (b) } 95 \%} & {\text { (d) } 47.5 \%}\end{array}$

Nathan J.

Intro Stats / AP Statistics

13Â hours ago

An airline flies the same route at the same time each day. The flight time varies according to a Normal distribution with unknown mean and standard deviation. On 15% of days, the flight takes more than an hour. On 3% of days, the flight lasts 75 minutes or more. Use this information to determine the mean and standard deviation of the flight time distribution.

James E.

Intro Stats / AP Statistics

13Â hours ago

Length of pregnancies The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 266 days and standard deviation 16 days. For each part, follow the four-step process. (a) At what percentile is a pregnancy that lasts 240 days (thatâ€™s about 8 months)? (b) What percent of pregnancies last between 240 and 270 days (roughly between 8 months and 9 months)? (c) How long do the longest 20% of pregnancies last?

Alexis C.

Intro Stats / AP Statistics

13Â hours ago

For Exercises 47 to 50, use Table A to find the proportion of observations from the standard Normal distribution that satisfies each of the following statements. In each case, sketch a standard Normal curve and shade the area under the curve that is the answer to the question. Use your calculator or the Normal Curve applet to check your answers. More Table A practice a) $z$ is between $-2.05$ and 0.78 b) $z$ is between $-1.11$ and $-0.32$

Alex T.

Intro Stats / AP Statistics

13Â hours ago

Measure up Clarence measures the diameter of each tennis ball in a bag with a standard ruler. Unfortu- nately, he uses the ruler incorrectly so that each of his measurements is 0.2 inches too large. Clarenceâ€™s data had a mean of 3.2 inches and a standard deviation of 0.1 inches. Find the mean and standard deviation of the corrected measurements in centimeters (recall that 1 inch = 2.54 cm).

Hania K.

Intro Stats / AP Statistics

17Â hours ago

Determine the mean and standard deviation of the random variable in each of the binomial distributions: a. = 4 and = 0.10 b. = 5 and = 0.80 c. = 3 and = 0.50

Veronica R.

Intro Stats / AP Statistics

1Â day, 4Â hours ago

A customer service representative must spend different amounts of time with each customer to resolve various concerns. The amount of time spent with each customer can be modeled by the following distribution: X ~ Exp(0.4). Find P(x > 5). (Round your answer to four decimal places.)

Veronica R.

Intro Stats / AP Statistics

1Â day, 4Â hours ago

A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24 pounds, and the highest is 26 pounds. Each weight is equally likely so the distribution of weights is uniform. A sample of 100 weights is taken. Find the 75th percentile for the mean weight for the 100 weights. (Round your answer to two decimal places.) ____lb

Veronica R.

Intro Stats / AP Statistics

1Â day, 4Â hours ago

An unknown distribution has a mean of 80 and a standard deviation of 12. A sample size of 95 is drawn randomly from the population. Find the sum that is 1.9 standard deviations below the mean of the sums. (Round your answer to two decimal places.)

0

0

0

Ask unlimited questions

Test yourself

Join Study Groups

Create your own study plan

Join live cram sessions

Live student success coach