Prob-5 The lighting department of a city has installed 2000 electric lamps with an average life of 10,000 h and a standard deviation of 500 h. After what period of lighting hours would we expect 65.54% of the lamps to fail? Assume life of lamps are normally distributed. Sol: 50% 65,54%

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018
18th Edition
ISBN:9780079039897
Author:Carter
Publisher:Carter
Chapter10: Statistics
Section10.3: Measures Of Spread
Problem 3CYU
icon
Related questions
Question

please answer question below step by step

Prob-5
The lighting department of a city has installed 2000 electric lamps with an average life of 10,000 h and a standard deviation of 500 h.
After what period of lighting hours would we expect 65.54% of the lamps to fail? Assume life of lamps are normally distributed.
Sol:
50% 65,54%
Transcribed Image Text:Prob-5 The lighting department of a city has installed 2000 electric lamps with an average life of 10,000 h and a standard deviation of 500 h. After what period of lighting hours would we expect 65.54% of the lamps to fail? Assume life of lamps are normally distributed. Sol: 50% 65,54%
Expert Solution
steps

Step by step

Solved in 3 steps with 1 images

Blurred answer
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897…
Glencoe Algebra 1, Student Edition, 9780079039897…
Algebra
ISBN:
9780079039897
Author:
Carter
Publisher:
McGraw Hill