Let's take XI, X2 ... Хой a radom sample of distribution defined in from the uniform (0, 0+1). Is the predictor &=-= Calculate the variance ? the interval)

th A scientist studying babies born prematurely would like to obtain an estimate for the mean birth weight, µ, of babies born during the 24"" week of the gestation period. She plans to select a random sample of birth weights of such babies and use the mean of the sample to estimate u. Assuming that the population of th birth weights of babies born during the 24"" week has a standard deviation of 2.6 pounds, what is the minimum sample size needed for the scientist to be 95% confident that her estimate is within 0.5 pounds of µ? Carry your intermediate computations to at least three decimal places. Write your answer as a whole number (and make sure that it is the minimum whole number that satisfies the requirements). (If necessary, consult a list of formulas.) Continue Submit As

Suppose that the duration of a particular type of criminal trial is known to be normally distributed with a mean of 21 days and a standard deviation of seven days. (a) In words, define the random variable X. Edit Insert Formats BIUX₂ + 2+ 3 = C P & (b) Find the z-score for a trial lasting 19 days. your answer to three decimal places.) Shade: Left of a value (c) If one of the trials is randomly chosen, find the probability that it lasted at least 19 days. +||||||||| (d) Shade the area corresponding to this probability in the graph below. (Hint: The x- axis is the z-score. Use your z-score from part (b), rounded to one decimal place). -1 X² A ▾ A▾ -1.5 用 Σ+ Σ Α 2 Click and drag the arrows to adjust the values. (Round ++++++++++++ 3 4 (e) eighty-eight percent of all trials of this type are completed within how many days?

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A population has a mean p= 160 and a standard deviation o=22. Find the mean and standard deviation of the sampling distribution of sample means with sample size n= 45. The mean is H- = |, and the standard deviation is o- = (Round to three decimal places as needed.)

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