S3A S3B S3C
Pass 22 25 20
Fail 4 1012
a)if 2 student are chosen at ramdom,find the pro of ↓events
i)both students pass the examination
ii)both students are from 3A,given that they pass the exam
b)if a class is chosen at ramdom from those three classes,then two student s are chosen at ramdom from a class,find the pro of ↓events
i)both students pass the examination
ii)both students are from 3A,given that they pass the exam
更新1:
Fail 4 10 12
