15. The marks obtained by the students in an examination are a. as follows. Marks obtained 0-10 10-20 20-30 Frequency If the of x 5 15 20 30-40 40-50 50-60 20 10 mean of the data is 32.5 then calculate the value x b) Find the median class of this data .Find the modal class . d) show that the median marks is more than the mean marks
