PreCalculus
posted by Lucy on .
Consider a class with 10 sophomores, 8 juniors, and 6 seniors. Two students are selected at random.
1) What is the probability of selecting 1 junior and 1 senior.
2) Find the odds of selecting two students who are not seniors.
How do I set these up to solve??
Any help is greatly appreciated!!

the total students are 24.
Probability of 1junior and 1 senior are..
Pr=(8/24)(6/23)
The second:
Pr=(18/24)(17/23)
Notice in each, the numerator is the number of possible ways to be successful,the denominator is the number of ways it can go. 
For number one, there is a total of 24 students when you add 10+8+6. Then you want to find 1 junior and 1 senior which added up becomes 2. soo....
2/24 = 1/12 reduced! :)