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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

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प्रश्न

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?

विकल्प

  • 0.214

  • 0.214

  • 0933

  • 0.067

MCQ
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उत्तर

0.067

shaalaa.com
Distribution
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Probability Distributions - Exercise 7.4 [पृष्ठ १७०]

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सामाचीर कलवी Business Mathematics and Statistics [English] Class 12 TN Board
अध्याय 7 Probability Distributions
Exercise 7.4 | Q 18 | पृष्ठ १७०

संबंधित प्रश्न

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