(a) In a manufacturing process, the diameter of steel rods is distributed normally with a mean value of 5 mm and standard deviation of 0.1 mm. If a rod is selected at random, what is the probability that its diameter will be: (i) less than 4.85 mm; (ii) between 4.9 mm and 5.1 mm? (b) A telephone exchange receives an average of 5 calls per minute. Calculate the probability that, in a given minute, the exchange receives: (i) exactly 5 calls; (ii) 2 calls or fewer

(a) In a manufacturing process, the diameter of steel rods is distributed normally with a mean value of 5 mm and standard deviation of 0.1 mm. If a rod is selected at random, what is the probability that its diameter will be: (i) less than 4.85 mm; (ii) between 4.9 mm and 5.1 mm? (b) A telephone exchange receives an average of 5 calls per minute. Calculate the probability that, in a given minute, the exchange receives: (i) exactly 5 calls; (ii) 2 calls or fewer

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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