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 at most 40? Greater than 60? b.? ?What yield strength value separates the strongest 75% from the others?

Answer Step 1 of 3 Given = 43 and = 4.5 a) The probability that yield strength is at most 40 Z=(x-)/ =(40-43)/4.5 =-0.67 P(x40)=P(z-0.67) =0.2514 The probability that yield strength is at most 40 is 0.2514 Step 2 of 3 The probability that yield strength is Greater than 60 Z=(x-)/ =(60-43)/4.5 =3.78 P(x60)=P(z3.78) =0 The probability that yield strength is Greater than 60 is 0