Question 389443: Please help! I don't understand where to begin the problem and the "at least one male student" is confusing me!!
Problem:
You are attending two classes this summer. Suppose the first class has 28 students and second class has 25 students. There are 15 females in the first class and there are 12 males in the second class. How many different ways could you select two groups of 3 students (one from each class) so that in each group you must have at least 1 male student?
Answer by sudhanshu_kmr(1152)   (Show Source):
You can put this solution on YOUR website!
In first class 28 students, 15 females and 13 males.
In second class 25 students, 13 females and 12 males.
Here in each group must have at least 1 males.....
For first class....
no. of ways to select a group of 3 students from first class =28C3 - 15C3
here 28C3 is the no. of ways to select a group without any restriction.
and 15C3 is the no. of ways to select a group where all are females, no male.
so, we will eliminate those no. of ways in which all are females.
Now, understand the concept and find the no. of possible groups for second class yourself.
you are welcome for any assistance: sudhanshu.cochin@gmail.com
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