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Tamil Nadu Board of Secondary EducationHSC Commerce Class 12

Choose the correct alternative: A statistical analysis of long-distance telephone calls indicates that the length of these calls is normally distributed with a mean of - Business Mathematics and Statistics

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Question

Choose the correct alternative:

A statistical analysis of long-distance telephone calls indicates that the length of these calls is normally distributed with a mean of 240 seconds and a standard deviation of 40 seconds. What proportion of calls lasts less than 180 seconds?

Options

  • 0.214

  • 0.214

  • 0933

  • 0.067

MCQ
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Solution

0.067

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Distribution
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Chapter 7: Probability Distributions - Exercise 7.4 [Page 170]

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Samacheer Kalvi Business Mathematics and Statistics [English] Class 12 TN Board
Chapter 7 Probability Distributions
Exercise 7.4 | Q 18 | Page 170

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