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Paragraph : The number of telephone calls received in 245 successive one minute intervals at an exchange is given below in the following frequency distribution. array |l|l|l|l|l|l|l|l|l| array l Number of calls array & 0 & 1 & 2 & 3 & 4 & 5 & 6 & 7 Frequency & 14 & 21 & 25 & 43 & 51 & 40 & 39 & 12 array Question : What is the mean of the distribution?

Options

  1. A3.76
  2. B3.84
  3. C3.96
  4. D4.05

Correct answer

A. 3.76

Step-by-step solution

array |c|c|c| x & f & f x 0 & 14 & 0 1 & 21 & 21 2 & 25 & 50 3 & 43 & 129 4 & 51 & 204 5 & 40 & 200 6 & 39 & 234 7 & 12 & 84 2 - 3 & 245 & 922 array Mean = 922 245 =3.76

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