First the mode will be  7-8 because the maximum frequency is   85
the median is if the no of  observations is  odd then formula is n+1/2
if even then mean of n/2 and n+1/2
so the no of observations means frequency is  217 it is odd so the formula is  n+1/2 so 217+1/2=
218/2=19 th term  so 19 th term is  5-6 so it is median
and mean=sum of observations /no of observations