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Confidence Interval Problem: Sample Size for Sales Call Logs

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Question: A company wants to estimate the average number of sales calls received daily. They want to be within 10 of the true mean when using a confidence interval of 95%. The standard deviation is estimated at 20.

How many daily call logs must they sample?

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Solution Summary

This solution provides assistance with the confidence interval problem.

Solution provided by:
Sandhya Sharma, MSc
Education
  • BSc, Meerut University
  • MSc, Meerut University
  • MPhil, Institute of Advanced Studies
  • MSc, AIT
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