Steel used for water pipelines is sometimes coated on the inside with cement mortar to prevent corrosion. In a study of the mortar coatings of a pipeline used in a water transmission project, the mortar thicknesses were measured for a very large number of specimens. The mean and the standard deviation were found to be 0.62 inch and 0.13 inch, respectively, and the thickness was found to be normally distributed. a) In what percentage of the pipelines is the thickness of mortar less than 0.5 inch? b) If four pipes are selected at random, what is the probability that two or more have mortar thickness less than 0.5 inch? c) 100 pipes are taken and their mortar thicknesses are measured individually. If the mortar thickness of a pipe is found to be less than 0.5 inch, 10% less is paid to the manufacturer for that pipe. If the normal price of a pipe is $125.00, what is the expected cost of 100 pipes?
Steel used for water pipelines is sometimes coated on the inside with cement mortar to prevent corrosion. In a study of the mortar coatings of a pipeline used in a water transmission project, the mortar thicknesses were measured for a very large number of specimens. The mean and the standard deviation were found to be 0.62 inch and 0.13 inch, respectively, and the thickness was found to be normally distributed. a) In what percentage of the pipelines is the thickness of mortar less than 0.5 inch? b) If four pipes are selected at random, what is the probability that two or more have mortar thickness less than 0.5 inch? c) 100 pipes are taken and their mortar thicknesses are measured individually. If the mortar thickness of a pipe is found to be less than 0.5 inch, 10% less is paid to the manufacturer for that pipe. If the normal price of a pipe is $125.00, what is the expected cost of 100 pipes?
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...
Related questions
Question
Transcribed Image Text:Steel used for water pipelines is sometimes coated on the inside with cement mortar to prevent
corrosion. In a study of the mortar coatings of a pipeline used in a water transmission project, the
mortar thicknesses were measured for a very large number of specimens. The mean and the
standard deviation were found to be 0.62 inch and 0.13 inch, respectively, and the thickness was
found to be normally distributed.
a) In what percentage of the pipelines is the thickness of mortar less than 0.5 inch?
b)
If four pipes are selected at random, what is the probability that two or more have mortar
thickness less than 0.5 inch?
c)
100 pipes are taken and their mortar thicknesses are measured individually. If the mortar
thickness of a pipe is found to be less than 0.5 inch, 10% less is paid to the manufacturer
for that pipe. If the normal price of a pipe is $125.00, what is the expected cost of 100
pipes?
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 4 steps with 9 images
Recommended textbooks for you
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON