In: Statistics and Probability
The article “Monte Carlo Simulation—Tool for Better Understanding of LRFD” (J. of Structural Engr., 1993: 1586–1599) suggests that yield strength (ksi) for A36 grade steel is normally distributed with ? = 43 and ? = 4.5.
a. What is the probability that yield strength is greater than 58?
b. What yield strength value separates the strongest 75% from the others?
c. what is the probability that the thread length of a randomly selected bolt is Within 1.5 SDs of its mean value?
Refer Standard normal table/Z-table to find the probability or use excel formula "=NORM.S.DIST(3.33, TRUE)" to find the probability.
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Refer Standard normal table/Z-table, Lookup for Z-value corresponding to area 0.75 to the right of the normal curve or use excel formula "=NORM.S.INV(1-0.75)" to find the Z-value.
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Refer Standard normal table/Z-table to find the probability or use excel formula "=NORM.S.DIST(1.5, TRUE)" & "=NORM.S.DIST(1.5, TRUE)" to find the probability.