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MATH SOLVE
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General
A university claims its recent graduates earn an average annual salary of $50,000. You draw a random sample of 30 recent graduates and find that their average salary is $47,000, with a standard deviation of $5,000. What is the estimate of the standard error of the mean for this data?
General
1 month ago
ABC Company has made a claim that, on average, their diet soda has less than one calorie. A consumer testing service examined nine cans, and the amount of calories recorded were 0.90, 0.95, 1.00, 1.05, 0.85, 1.00, 0.95, 0.95 and 0.90. Assume the underlying population is approximately normal. a. What are the sample mean and sample standard deviation, respectively?b. Let μ denote the true mean calories of all diet sodas produced by ABC Company. What hypothesis should be tested in order to show if ABC’s claim is valid?c. The appropriate statistic to test this hypothesis is ______d. The value of the test statistic is ______e. The appropriate number of degrees of freedom for this test statistic is ______f. What conclusion can be made with 95% confidence?
General
1 month ago
Which of the following is an equation for the line that passes through the point (0,0) and is perpendicular to the line shown above ?
General
1 month ago
Scores on the SAT college entrance test in a recent year were roughly Normal with mean 1026 and standard deviation 209. You choose an SRS of 100 students and find their average SAT score, x-bar. If you repeatedly take SRS of 100 students and calculate x-bar for each sample, then the mean of the sampling distribution you create will be closest to
General
1 month ago
Verify that the given vector field h is a gradient. Then calculate the line integral of h over the indicated curve C by finding f such that the gradient f = h and evaluating f at the end points of C.h(x,y) = xy^2 i + yx^2 jr(u) = u i + 2u^2 j0 ? u ? 1Please show all the steps so that I will know where i am making a mistake. I have attempted this question 4 times and i do not know where am going wrong. The correct answer is 2. I keep getting 4.
General
1 month ago
A very large gardening business grows rose bushes for sale to garden stores around the world. The most popular colors are red, pink, and white. The business decides on 50% red roses, 30% pink, and 20% white. A gardener orders 10 rose bushes selected randomly from a huge field. Her primary interest is in pink roses. A good model for the number of bushes with pink roses is given by the binomial distribution.The probability of getting at least 3 pink rose bushes is: (a) 0.5. (b) 0.617. (c) 0.348. (d) 0.259.
General
1 month ago
A random sample of 500 adult residents of Maricopa County found that 356 were in favor of increasing the highway speed limit to 75 mph, while another sample of 400 adult residents of Pima County found that 297 were in favor of the increased speed limit. Do these data indicate that there is a difference in the support for in increasing the speed limit between the residents of the two counties? Use α = 0.05.a) do these data indicate that there is a difference in thesupport for increasing the speed limit between residents of the twocounties? Use α = 0.05. What is the P-value forthis test?b) construct a 95% confidence interval on the difference inthe two proportions. Provide a practical interpretation ofthis interval.Please show formulas
General
1 month ago
Assume that the following confidence interval for the difference in the mean length of male (sample 1) and female babies (sample 2) at birth was constructed using independent simple random samples. What does the confidence interval suggest about the difference in length between male babies and female babies? minus −0.2 in. less than < mu 1 μ1 minus − mu 2 μ2 less than <1.7 in.a female babies are longerb male babies are longerc there is no difference in the length between male and female babies
General
1 month ago
In a recent year, a poll asked 2362 random adult citizens of a large country how they rated economic conditions. In the poll, 22% rated the economy as Excellent/Good. A recent media outlet claimed that the percentage of citizens who felt the economy was in Excellent/Good shape was 24%. Does the poll support this claim? a) Test the appropriate hypothesis. Find a 99% confidence interval for the proportion of adults who rated the economy as Excellent/Good. Check conditions. b) Does your confidence interval provide evidence to support the claim? c) What is the significance level of the test in b? Explain.
General
1 month ago
Parking Hoping to lure more shoppers downtown, a city builds a new public parking garage in the central business district. The city plans to pay for the structure through parking fees. Dur-ing a two-month period (44 weekdays), daily fees collected av-eraged $126, with a standard deviation of $15. a) What assumptions must you make in order to use these statistics for inference? b) Write a 90% confidence interval for the mean daily income this parking garage will generate. c) Interpret this confidence interval in context. d) Explain what "90% confidence" means in this context. e) The consultant who advised the city on this project predicted that parking revenues would average $130 per day. Based on your confidence interval, do you think the consultant was correct? Why?
General
1 month ago
A volleyball league collected $2,040 for both division of volleyball teams the blue division costs &160 per team and the red division costs $180 per team.how many teams will play in each division
General
1 month ago
A volleyball league organizer collected $2,040 for both divisions of volleyball teams.teams.the blue division costs &160 per team and the red division costs $180 per team how many teams will play in each division
General
1 month ago
Sally invested money into two different accounts at the same time. The system of inequalities represents the balance of each account where x represents the number of years the money has been invested.Account A: y≥1.13x+1000Account B: y≥1.08x+1000What is true in the context of the situation based on the system of inequalities?Select True or False for each statement.Statement True FalseSally initially invests more money into Account A than Account B.The rate at which the balance of Account A grows is greater than the rate at which the balance of Account B grows.Sally invests a total of $1000 into the two accounts.
General
1 month ago
A hotel chain wants to estimate the average number of rooms rented daily in each month. The population of rooms rented daily is assumed to be normally distributed for each month with a standard deviation of 24 rooms. During June, a sample of 16 days has a sample mean of 48 rooms. This information is used to calculated an interval estimate for the population mean to be from 40 to 56 rooms. What is the level of confidence of this interval?
General
1 month ago
A new surgical procedure is said to be successful 60% of the time. Suppose the operation is performed nine times and the results are assumed to be independent of one another. What are the probabilities of these events? (Round your answers to three decimal places.)
General
1 month ago
a. Find the critical point of the given function and then determine whether it is a local maximum, local minimum, or saddle point.f(x, y) = x2 − y2 + 3xyb. Find the critical point of the given function and then determine whether it is a local maximum, local minimum, or saddle point.f(x, y) = x2 + y2 − xy
General
1 month ago
A New York Times article titled For Runners, Soft Ground Can Be Hard on the Body considered two perspectives on whether runners should stick to hard surfaces or soft surfaces following an injury. One position supported running on soft surfaces to relieve joints that were in recovery from injury. The second position supported running on hard surfaces since soft surfaces can be uneven, which may make worse those injuries a soft surface was intended to help. Suppose we are given sufficient funds to run an experiment to study this topic. With no studies to support either position, which of the following hypotheses would be appropriate? A.The second position makes the more sense, so this should be a one-sided test. In this case, we should form the alternative hypothesis around the first position.B. The first position is more sensible, so this should postpone defining the hypotheses until after we collect data to guide the rest.C. Because there is uncertainty, we should postpone defining the hypotheses until after we collect data to guide the test.D. Because we would be interested in any difference between running on hard and soft surfaces, we should use a two-sided hypothesis test
General
1 month ago
Use the Midpoint Rule with the given value of n to approximate the integral. Round the answer to four decimal places. 64 0 sin( x ) dx, n = 4
General
1 month ago
A manufacturer must decide whether to build a small or a large plant at a new location. Demand at the location can be either low or high, with probabilities estimated to be 0.4 and 0.6, respectively. If a small plant is built, and demand is high, the production manager may choose to maintain the current size or to expand. The net present value of profits is $223,000 if the firm chooses not to expand. However, if the firm chooses to expand, there is a 50% chance that the net present value of the returns will be 330,000 and a 50% chance the estimated net present value of profits will be $210,000. If a small facility is built and demand is low, there is no reason to expand and the net present value of the profits is $200,000. However, if a large facility is built and the demand turns out to be low, the choice is to do nothing with a net present value of $40,000 or to stimulate demand through local advertising. The response to advertising can be either modest with a probability of .3 or favorable with a probability of .7. If the response to advertising is modest, the net present value of the profits is $20,000. However, if the response to advertising is favorable, then the net present value of the profits is $220,000. Finally, if the large plant is built and the demand happens to be high, the net present value of the profits $800,000a) Draw a decision tree b) Determine the payoff for each decision and event node. Which alternative should the manufacturer choose?
General
1 month ago
If on a scale drawing 75 feet are represented by 45 inches, then a scale of 1/5 inch represents how many feet?
General
1 month ago
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