(1) When the collected data are taken continuously, we usually group the data appropriately first, and then draw the histogram of frequency distribution.

(2) The general steps of drawing frequency distribution histogram: ① Calculate the difference (range) between the maximum value and the minimum value, and determine the statistical range; (2) Determine the number and distance of groups. The more data, the more groups. ③ Determine the demarcation point; ④ Column frequency distribution table; ⑤ Draw the histogram of frequency distribution.