# 11. Following is the distribution of marks obtained by 60 students: Calculate the arithmetic meanMarksMorethan 0more than 10More than20More than 30More than 40More than 50No ofstudents60564020103

xThe table can be given as,

 More than Cumulative frequency Class frequency(fi) fi.xi More than 0 60 0-10 4 20 More than 10 56 10-20 16 240 More than 20 40 20-30 20 500 More than 30 20 30-40 10 350 More than 40 10 40-50 7 315 More than 50 3 50-60 3 165

Now using direct method for finding the mean of 60 student,

Mean = $\frac{1590}{60}=26.5$

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