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In Problems 17–20, find the mean, variance, and standard deviation.
19.
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- 1. In an epidemic, the probability of having S|D is 0.2 and P(D) = 0.1. P(S|D') = 0.04 and P (D') = 0.01. What is the P(D|S)? 2. The relationship between weight and age was found to have a linear relationship, with expression weight= 3.0 (age) +10. Predict the weight of a girl whose age is 20 years? 3. A. If a z score of 1.95 is equal to a p of 0.9744, what proportion is greater than1.95 B. From question A, what proportion is between the mean and 1.95? 4. If a the constant for a regression is 0.8 and the standard deviation for the x variables is 4 while the standard deviation for the y variables is 6. What is the correlation coefficient r? 5. In a class of 20 students, twelve take mathematics and genetics, while eight take genetics only. What is the probability of selecting a student who takes only mathematics?arrow_forward5. Let X have the pdf (x + 1) -1 < x < 1 f(x) = %3D elsewhere. Find the mean and the variance of X.arrow_forward6. Find the mean and variance of fx (x) = 2e eA* la.2...) (x) = dearrow_forward
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