The strength of a weld is determined by the formula X = 0 + 3N + 5C where X is the strength, and O, N, and C are the amounts of oxygen, nitrogen, and carbon, respectively in weight per cent in the weld. Suppose O, N and C are Independent normal random variables with respective means µ0 = 0.1665, µN = 0.0455, µC = .0346, and standard deviations o0 = 0.0340, oN = 0.0114, oC = .0131 a) Calculate the expected value of X. 0.476 b) Calculate the standard deviation of X. 0.0813 c) What is the probability that the strength(X) of a weld is more than 0.5? 0.384 d) What is the probability that the strength of a weld is between 0.4 and 0.6.? 0.761 e) If we pick a value k such that the probability that X > k equals .87 then calculate k? f) What is the median of the distribution of X? g )We look at 10 randomly selected welds. What is the probability that all 10 of the selected welds have strengths greater than .467? h) What is the probability that the strength of a weld is exactly .480? I) What is the probability that N > 0.05?

The strength of a weld is determined by the formula X = 0 + 3N + 5C where X is the strength, and O, N, and C are the amounts of oxygen, nitrogen, and carbon, respectively in weight per cent in the weld. Suppose O, N and C are Independent normal random variables with respective means µ0 = 0.1665, µN = 0.0455, µC = .0346, and standard deviations o0 = 0.0340, oN = 0.0114, oC = .0131 a) Calculate the expected value of X. 0.476 b) Calculate the standard deviation of X. 0.0813 c) What is the probability that the strength(X) of a weld is more than 0.5? 0.384 d) What is the probability that the strength of a weld is between 0.4 and 0.6.? 0.761 e) If we pick a value k such that the probability that X > k equals .87 then calculate k? f) What is the median of the distribution of X? g )We look at 10 randomly selected welds. What is the probability that all 10 of the selected welds have strengths greater than .467? h) What is the probability that the strength of a weld is exactly .480? I) What is the probability that N > 0.05?

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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