阅读下面这首古诗，回答下面两题。
                                                                                                                                            闽中秋思
                                                                                                                                      （唐）杜荀鹤
                                                                                                                      雨匀紫菊丛丛色，风弄红蕉叶叶声。
                                                                                                                      北畔是山南畔海，只堪图画不堪行。

某校从参加高一年级期中考试的学生中随机抽取60名学生，将其数学成绩（均为整数）分成六段40，50），50，60）…90，100后得到如下部分频率分布直方图．观察图形的信息，回答下列问题：