120 surnames were randomly picked up from a local telephone directory. And the frequency distribution of the number of letters in the English alphabets in the surnames were recorded as. ( given in the below table). If the mean of the. data is 7 find the missing frequencies x and y

Dear Student ,
Please find below the solution to the asked query :

109+x+y=120x+y=11x=11-y   ...1Mean=fixifi7=742.5+1.5x+16.5y1207×120=742.5+1.5 11-y+16.5y      using 1840=742.5+16.5-1.5y+16.5y840=759+15y840-759=15y81=15yy=8115=5.4x=11-5.4=5.6Number of surnames can't be in decimal please recheck your question.
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