If the middle 70% of the scores about the mean represent healthy people then what are the Lower, L, and Upper, U, cut-off scores for being healthy. L = ___________; U = ________________

i couldnt know how to solve it I wanna know with steps

Do question 1

Suppose the scores on an exam have a mean of 70 with a standard deviation of 10. If one student hasa test result with a z-score of -0.8 and a second student has a test result with a Z-score of 1.8, how many points higher was the second student's score than that of the first? O a. 10 O b. 20 O c. 2.6 O d. 13 O e. 26

We'd like to compare two populations A and B. Population A has a mean of 40 and a standard deviation of 4. Population B has a mean of 50 and a standard deviation of 7. We will randomly select a sample of size 100 from population A, and a sample of size 100 from population B. What is the standard deviation of the difference of sample means? So, you need to find op where D =XA-Xg. Round your answers with 2 decimal digits after the decimal point, like 8.23, or 0.92, etc.

For numbers 31-37, refer to the given problem. The average time it takes for a group of college students to complete a certain examination is 46.2 minutes whereas the standard deviation is 8 minutes. Fifty college students were randomly selected to take the examination. Assume that the variable is normally distributed. What is the probability that the mean time it takes for the group to complete the test will be less than 43 minutes? 31. What is the population mean u? B. 43 A. 8 C. 46.2 D. 50 32. What is the population standard deviation a? А. 8 В. 43 C. 46.2 D. 50 33. What is the sample size n? А. 8 B. 43 C. 46.2 D. 50 34. What is asked in the given problem? A. P(X 43) D. P(>43) 35. What formula is to be used in finding the z-score? D. z = X-4 VIL H-X B. Z = X- C. z = -8 A. z = of 36. What is the answer to the question? В. 15.54% A. 0.23% С. 23% D. 34.46%

Find the indicated IQ score. The graph to the right depicts IQ scores of adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15. Click to view page 1 of the table. Click to view page 2of tihe fable 0.9 The indicated IQ score, x, is (Round to one decimal place as needed.)

Hemoglobin levels in adult males are normally distributed with a mean of 14.5 g/dL and a standard deviation of 0.6 g/dL. The normal hemoglobin range for men is 13.8 g/dL to 14.9 g/dL. What percentage of men have hemoglobin levels in the normal range? Round your answer to four decimal places.  If we randomly collect samples of men with 19 in each sample, what percentage of those samples have a mean hemoglobin level that is within the normal range? Round your answer to four decimal places

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80 84 94 65 72 55 84 99 86 87 For this population answer the following 6 questions. 1. Find U=. 2. Find O - %3D 3. Find the standard deviation = 4. Find the Z-score of 75. 5. How many standard deviations from the mean is the score of 62? 6. What score represents a Z-score of -2 for this popuiation? shows thos ve