Median is to arrange all samples from small to large, and the sample values are distributed in the middle (total * * * odd samples) or the average value of two sample values in the middle (total * * * even samples).

For this kind of histogram without specific data, find the sample value whose frequency accumulates from small to large to 0.5.

Because there is no specific total number of samples, it can be considered that the topic will not make 0.5 in the boundary, but within a certain sample value.

Figure A, 7+8 = 0.35; 7+8+9=0.65, and the median is 9.

Figure b, 7+8 = 0.45; 7+8+9=0.65, and the median is 9.