WBBSEClass XMathematicsStatistics02 Mark2024 Easy

QQuestion

The mean of a frequency distribution is 7 and Σfx = 140, then find the value of Σf

Exam-ready answer 02 Mark

Answer

Mean = Σfx / Σf

⇒  7 = 140 / Σf

⇒ Σf = 140 / 7 = 20

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