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In Problems 17–20, find the mean, variance, and standard deviation.
17.
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Calculus for Business, Economics, Life Sciences, and Social Sciences (14th Edition)
- 2 3: If u(x) = 8 for 0sxs100 find the mean, mode and median of the age 100 -x 400-x at death of a newborn.arrow_forward6. An optical device is used to detect the passage of cars in a single lane of a downtown street. Because there must be at least half a second between successive cars, it is assumed that the times T; between = 0.50 + Si, where S1, S2, ··. are independent exponential (A) random cars are of the form T; variables. (a) Find the mean and variance of each T;. (b) Let Y, be the time at which the nth car passes the detector. Calculate the mean and variance of Yn. (c) Under what conditions is Yn approximately normally distributed and why? (d) When n = 50 and A = 0.10, calculate the approximate probability that Yn exceeds 500 seconds.arrow_forwardSituation 9. Suppose that X has a lognormal distribution with parameters 0 = -2 and ² = 9. Determine the following: 18. P(500 x) = 0.1 20. The variance of X.arrow_forward
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- Example 9-32. Show that the mean value of positive square root of a y (u) variate is T(u +; )/T(µ). Hence prove that the mean deviation of a normal variate from its mean is V2/T , where o is the standard deviation of the distribution.arrow_forwardProb. 3 Let X be a random variable with cumulative distribution function (cdf) given by (1-e-x², x ≥ 0 ={1,- x<0 Find the probability that the random variable X falls within one standard deviation of its mean. Fx (x) =arrow_forwardSuppose the relationship between Y and X is given by: Y = 25 - 3X + error By how much does the expected value of Y change if X decreases by 2 units?arrow_forward
- Calculus For The Life SciencesCalculusISBN:9780321964038Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.Publisher:Pearson Addison Wesley,