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Madison bought an empty lot for $2,000 and later sold it for a 25% profit. How much did Madison sell the lot for? A) $500 B) $1,500 C) $2,500 D) $3,000
General
1 month ago
A simple game goes as follows: you pay one dollar and roll a die. If the roll is either a 1 or 2, you get your dollar back. If it is greater than 3 you lose the dollar you paid. If it is a 3, you get your dollar back and an additional dollar. What is the expected value of the net amount of money you win/lose?
General
1 month ago
Suppose that two populations have the same mean. A researcher draws a sample of size 35 from each population and calculates the difference in sample means. He then repeats this process 99 more times, resulting in 100 calculated differences in sample means. The researcher finds the standard error of the difference in sample means to be 1.78. Which of the following statements is true regarding the distribution of the differences in sample means? The center of the distribution will be approximately 0, with about 68 percent of the differences in means between -3.56 and 3.56
General
1 month ago
A researcher developing scanners to search for hidden weapons at airports has concluded that a new device is significantly better than the current scanner. He made this decision based on a test using a = 0.05. Would he have made the same decision at a = 0.10? How about a = 0.01? Explain.
General
1 month ago
An SRS of 25 recent birth records at the local hospital was selected. In the sample, the average birth weight was = 119.6 ounces. Suppose the standard deviation is known to be σ = 6.5 ounces. Assume that in the population of all babies born in this hospital, the birth weights follow a Normal distribution, with mean μ. Based on the 25 recent birth records, the sampling distribution of the sample mean can be represented by:A. N(μ, 6.5).B. N(μ, 1.30).C. N(119.6, 1.30).D. N(119.6, 6.5).
General
1 month ago
The owner of a large car dealership believes that the financial crisis decreased the number of customers visiting her dealership. The dealership has historically had 800 customers per day. The owner takes a sample of 100 days and finds the average number of customers visiting the dealership per day was 750. Assume that the population standard deviation is 350. The value of the test statistic is ____________. Multiple Choice z = –1.429 t99 = 1.429 z = 1.429 t99 = –1.429
General
1 month ago
Find the absolute maximum and absolute minimum values of f on the given interval.a) f(t)= t sqrt(36-t^2) [-1,6]absolute max=absolute min=b) f(t)= 2 cos t + sin 2t [0,pi/2]absolute max=absolute min=
General
1 month ago
Ackerman & Goldsmith (2011) found that students who studied text from printed hard copy had better test scores than students who studied text presented on a screen. In a related study, a professor noticed that several students in a large class had purchased the e-book version of the course textbook. For the final exam, the overall average for the entire class was μ = 85, but the n = 10 students who purchased the e-book had a mean of M = 77 with a standard deviation of s = 6. Do these data indicate a significant decrease in test scores on the final exam due to the use of a e-book? Use a one-tailed test with α = .05.
General
1 month ago
Translate the following inequality into written language. 5x-6<14
General
1 month ago
PLEASE HELP 100PTS!!!!!!!! I SOLVED IT BUT I WANT TO CHECK MY ANSWERS!!DONT COPY OTHER ANSWERS I CAN TELL AND REPORT YOU!!!!A scientist is studying the growth of a particular species of plant. He writes the following equation to show the height of the plant f(n), in cm, after n days:f(n) = 10(1.02)nPart A: When the scientist concluded his study, the height of the plant was approximately 11.04 cm. What is a reasonable domain to plot the growth function?Part B: What is the average rate of change of the function f(n) from n = 1 to n = 5, and what does it represent?
General
1 month ago
A sample of 38 observations is selected from one population with a population standard deviation of 3.4. The sample mean is 100.5. A sample of 51 observations is selected from a second population with a population standard deviation of 5.8. The sample mean is 98.8. Conduct the following test of hypothesis using the 0.05 significance level. H0 : μ1 = μ2 H1 : μ1 ≠ μ2 a. This is a -tailed test. b. State the decision rule. (Negative values should be indicated by a minus sign. Round your answers to 2 decimal places.) c. Compute the value of the test statistic. (Round your answer to 2 decimal places. d. What is your decision regarding H0? e. What is the p-value? (Round your answer to 4 decimal places.)
General
1 month ago
A researcher wishes to estimate, with 95% confidence, the population proportion of adults who say chocolate is their favorite ice cream flavor. Her estimate must be accurate within 4% of the population proportion. (a) No preliminary estimate is available. Find the minimum sample size needed. (b) Find the minimum sample size needed, using a prior study that found that 38% of the respondents said their favorite flavor of ice cream is chocolate. (c) Compare the results from parts (a) and (b).
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1 month ago
A researcher is interested in estimating the mean weight of a semi tracker truck to determine the potential load capacity. She takes a random sample of 17 trucks and computes a sample mean of 20,000 pounds with sample standard deviation of 1,500. The 95% confidence interval for the population mean weight of a semi tracker truck is____________.
General
1 month ago
Ravi ordered some books online and spent a total of $89. Each book cost $5 and he paid a total of $4 for shipping. How many books did he buy?(a) Write an equation that could be used to answer the question above. First, choosethe appropriate form. Then, fill in the blanks with the numbers 89,5, and 4. Let brepresent the number of books.
General
1 month ago
Evaluate the Riemann sum for f(x) = 3x − 1, −6 ≤ x ≤ 4, with five subintervals, taking the sample points to be right endpoints.
General
1 month ago
What are the dimensions of the lightest open-top right circular cylindrical can that will hold a volume of 2744 cmcubed3?
General
1 month ago
Teresa has to buy school supplies for her 2 children, and wants to estimate the total cost of the school supplies. She knows that: Each child needs a backpack, a binder, 6 spirals, and 4 pens. The most expensive backpack is $57.00 dollars. The least expensive backpack is $29.00 dollars. The binders cost $4.00 each. The spirals cost $1.95 for three. The pens cost $0.48 each. There is 10% sales tax on her total purchase. Estimate how much money the school supplies will cost. A. $212.00 B. $232.00 C. $58.00 D. $116.00
General
1 month ago
Question OneFarmer Jones has 140 feet of fencing to construct a rectangular corral.If x represents the width of the corral, which function can be used to express the area A of thecorral as a function of x?AA(x) = 70.0BA(z) = 2(70 - 2)CA(x) = a(140 – 2)DA(z) = x(140 – 22)
General
1 month ago
A recent nationwide study investigated the value of the prostate-specific antigen (PSA) blood test for the detection of prostate cancer among 100,000 men 50 years of age and older. Of the 686 men who tested positive on the PSA test, a total of 281 were ultimately diagnosed with prostate cancer, either by immediate needle biopsy or during 12 months of watchful waiting. An additional 45 men who tested negative on the PSA test were ultimately diagnosed with prostate cancer during 12 months of follow-up.1) Set up the 2X2 contingency table for the data. 2) What is the sensitivity of the PSA test? Interpret the result.3) What is the specificity of the PSA test? Interpret the result.4) What is the positive predictive value (PPV) of the PSA test? Interpret the result.5) What is the negative predictive value (NPV) of the PSA test? Interpret the result.6)A screening test is available to identify individuals with a genetic mutation that puts them at greater risk for stroke. The test is extremely expensive and is not covered by most insurance plans, so those choosing to have the test usually have to pay for it out-of-pocket. However, it has been determined that the screening test is very valuable because the annual incidence of stroke among those who have been screened is nearly half that of the general population.7) One major benefit of mammography screening for breast cancer is that the disease is often diagnosed in the presymptomatic phase of the disease, before it is detectable by any other means, and breast cancers diagnosed in such early stages respond better to treatment. Another benefit of screening is that women diagnosed with breast cancer by way of mammography have better survival rates than women diagnosed by other means.8) The prognosis for neuroblastoma, a tumor that occurs in young children, varies greatly by patient. Some tumors are slow-growing and may even heal spontaneously. Others tumors are fast-growing and aggressive. A urine screening test for neuroblastoma is currently available that detects metabolites produced by the tumor. It has been suggested that such screening is highly valuable PH20001 Essentials of Epidemiology 2 because the case-fatality rate of neuroblastoma among children diagnosed with the urine test is much lower than it is for those who were not screened.9) Suppose that a new screening test has recently been developed to aid in the early identification of individuals with rheumatoid arthritis. However, the value of the test has not yet been established. In an effort to test the effectiveness of the new test in predicting a future diagnosis of rheumatoid arthritis, investigators enroll a group of volunteer participants, record their test result, and follow them forward for the development of the condition. It is subsequently determined that the new screening test is highly effective in predicting a definitive diagnosis of rheumatoid arthritis because the incidence of the condition among those who screened positive was much higher than that of the general population.10) There are at least a dozen types of human papillomaviruses (HPV) that are considered high-risk and cause approximately 5% of all cancers world-wide. However, high-risk HPV infections are common and most occur without any symptoms and resolve on their own within 1-2 years. In 2003, cervical HPV screening tests became available and are now approved for use in combination with a Pap test among women over the age of 30. Such tests can detect infection of several high-risk HPV types before cell changes become evident. Some argue that HPV screening tests should be approved for universal use among women of all ages because the incidence of high-risk HPV infections has increased dramatically over the past decade.
General
1 month ago
A pleasure boat sets out for a cruise on a river, sailing upstream 24 miles and then turning around and returning to port. The trip upstream requires 144 minutes and the trip downstream requires 40 minutes. Find the speed of the boat in still water and the speed of the current in miles per hour (mi/h). Round to the nearest whole number.
General
1 month ago
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