Question

Find the mean if x 4, 8,14,11,5 and f4,6,8,10,12

Answer 1

This is a case of mean for an ungrouped frequency distribution .
And in this case mean = x¯=x1f1+x2f2+x3f3+.......xnfnf1+f2+f3+..........fn  where x1,x2,......xn are the values of variables occuring with frequencies f1,f2....fn
So preparing the table for the given question-

xi             fi              xifi5               4               206               8               487               14             988               11             889                3              27 

∴Mean =(20+48+98+88+27)(5+6+7+8+9)=28135=8.02