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4. Suppose the standard deviation of the house Prices is $77,000. How much more expensive than the
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Intro Stats Plus Student Solutions Manual (4th Edition)
- The time that it takes a driver to react to the brake lights on a decelerating vehicle is critical in helping to avoid rear end collisions. A study found that the reaction time for an in traffic reponse to a brake signal from standard brake lights can be modeled with a normal distribution with a mean of 1.25 secs and standard deviation of 0.45 sec what percent of drivers have a reaction time longer than 2.15 seconds?arrow_forwarda research hypothesis is that the variance of stopping distances of automobiles on wetpavement is substantially greater than the variance of stopping distances of automobileson dry pavement. in the research study, 16 automobiles traveling at the same speeds aretested for stopping distances on wet pavement and then tested for stopping distances ondry pavement. on wet pavement, the standard deviation of stopping distances is 32 feet.on dry pavement, the standard deviation is 16 feet.a. at a .05 level of significance, do the sample data justify the conclusion that the variance in stopping distances on wet pavement is greater than the variance in stoppingdistances on dry pavement? what is the p-value?arrow_forwarda research hypothesis is that the variance of stopping distances of automobiles on wetpavement is substantially greater than the variance of stopping distances of automobileson dry pavement. in the research study, 16 automobiles traveling at the same speeds aretested for stopping distances on wet pavement and then tested for stopping distances ondry pavement. on wet pavement, the standard deviation of stopping distances is 32 feet.on dry pavement, the standard deviation is 16 feet.a. at a .05 level of significance, do the sample data justify the conclusion that the variance in stopping distances on wet pavement is greater than the variance in stoppingdistances on dry pavement? what is the p-value?b. what are the implications of your statistical conclusions in terms of driving safetyrecommendations?arrow_forward
- The scores of students on a standardized test form a normal distribution with a mean of 300 and a standard deviation of 40. Using the fact that the middle 50% of the data falls within .67 standard deviations from the mean, find the lower and upper quartile scores for this test.arrow_forwardThe IQ of 1,000 incoming students at University of Bayabas is normally distributed with a mean of 103 and a standard deviation of 10. Find and sketch the area of the normal curve of that is less than 115.arrow_forwardProfessor Smith took a sample of 210 students from her morning class and a sample of 163 students from her evening class. On Exam 1, all those sampled from the morning class got a 67 while those sampled from the evening class averaged a 67 with a variance of 127. If Professor Smith combines these two samples.What is the combined Exam 1 Average?What is the combined Exam 1 median?What is the combined Exam 1 Standard Deviation?arrow_forward
- The length of time of full-length movies is approximately normally distributed with a mean of 1.9 hours and standard deviation of 0.3 hours. Based on this scenario, explain what a Z-Score is.arrow_forwardA drug, which is used for treating cancer, has potentially dangerous side effects if it is taken in doses that are larger than the required dosage for the treatment. The tablet should contain 41.54mg and the standard deviation should be 0.04. 12 tablets are randomly selected and the amount of drug in each tablet is measured. The sample has a mean of 41.535mg and a variance of 0.0012mg. Does the data suggest at α=0.01 that the tablets vary by less than the desired amount? Step 1 of 5 : State of the hypotheses in terms of the standard deviation. Round the standard deviation to four decimal places when necessary Step 2 of 5 : Determine the critical value(s) of the test statistic. If the test is two-tailed, separate the values with a comma. Round your answer to three decimal places. Step 3 of 5 : Determine the value of the test statistic. Round your answer to three decimal places. Step 4 of 5 : Make the decision. Step 5 of 5 : What is the conclusion?arrow_forwardThe scores on a standardized test are normally distributed with a mean of 120 and standard deviation of 20. What test score is 2 standard deviations below the mean?arrow_forward
- An educational study to be conducted requires a test score in the middle 40% range. If the population mean equals 100 and the standard deviation equals 15, find the highest and lowest acceptable test scores that would enable a candidate to participate in the study. Assume the variable is normally distributed.arrow_forwardA random variable of 25 packs of powdered milk showed a mean content of 237 grams with a standard deviation of 8.56 grams while a sample of 20 packs of another brand of powdered milk showed a mean content of 240 grams with a standard deviation of 9.75 grams. Using a 0.05 level of significance, is there significant difference in the mean content of the two brands of powdered milk? Assumed variances are equal.arrow_forwardThe IQ of 1,000 incoming students at University of Bayabas is normally distributed with a mean of 103 and a standard deviation of 10. Find and sketch the area of the normal curve of that is between 60 and 130.arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill