Find the mean and variance for the following frequency distribution.
Classes $0-10$ $10-20$ $20-30$ $30-40$ $40-50$
Frequencies $5$ $8$ $15$ $16$ $6$

  • A
    Mean = $27$,Variance = $132$
  • B
    Mean = $25$,Variance = $132$
  • C
    Mean = $27$,Variance = $120$
  • D
    Mean = $28$,Variance = $132$

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