基 65题--求救

echosongling

41.A new type of graph question, 30 students in a certain, please refer to the above graphic which indicate the relationship between the no of students and the frequency they did certain activity (not accurate), ask what’s probability for a student to did certain activity more than 1 time of the median (or average!!友情提醒，一定要注意这个好像是Median我算成average了) of the group

横轴加起来不是30，所以猜测纵轴为学生数，横轴为频率

Median是大于8次的，〉8的学生有7+8=15人，

P=15/30=1/2

echosongling

median 不是是第15项+16项后除以2=8+10除以2=9

然后问的是： what’s probability for a student to did certain activity more than 1 time of the median of the group
P=7/30

因为7个学生时10，刚好是median 9+1=10


图表发不上来