Question

how do i find a median class for grouped frequency? is (total freq+1)/2 correct,

or do i have to count manually?
(like 1-5 freq is 20 and 6-10 is 35, so i count each and find a middle point)

Answer 1

There is an animated explanation here:
http://library.leeds.ac.uk/tutorials/maths-solutions/video_clips/stat_prob/averages/median_of_grouped_frequency_table.html