Arranging the values in an ascending order: 65-70, 65-70, 65-70, 70-75, 75-80, 75-80, 85-90, 85-90, 85-90, 90-95.

The number of the values is 3+1+2+3+1=10. The number of the values is even, therefore the median is the average of the groups in the positions 5 and 6. This is the group 75-80.

65-70, 65-70, 65-70, 70-75, 75-80, 75-80, 85-90, 85-90, 85-90, 90-95