SohnCo has a division that manufactures steel for construction uses. Recently, they have had some problems with their steel and look into some failures. The most probable strength of a steel beam is given by 24Y ―0.05 kips where Y is the number of cycles. This value is known to 25% with 90% confidence. a) How many cycles will elapse before the beam loses 20% of its strength? b) Suppose the cyclic load on the beam is 10 kips. How many cycles will occur before the probability of failure reaches 10%. Assume this can be described by a lognormal distribution.

SohnCo has a division that manufactures steel for construction uses. Recently, they have had some problems with their steel and look into some failures. The most probable strength of a steel beam is given by 24Y ―0.05 kips where Y is the number of cycles. This value is known to 25% with 90% confidence. a) How many cycles will elapse before the beam loses 20% of its strength? b) Suppose the cyclic load on the beam is 10 kips. How many cycles will occur before the probability of failure reaches 10%. Assume this can be described by a lognormal distribution.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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