probability help

[missemtee]

I really struggle with probability! I don't understand what I'm doing or why I'm doing it. Please help explain and answer this question.I got part a and d but not b and c.  I know it sounds so simple but I don't know how to do it   THANK YOU!!

The santaroos have 3 soccer teams, A,B of and C, entered in the interschool championships. Each team is entered in a seperate division. The probability of each team winning their particular final is given as follows:
Pr(Team A wins)= 1/2
Pr(Team B wins)= 1/3
Pr(Team C wins)= 3/4
Find the probability that:

a) none of the santaroos teams win
b) one of the santaroos teams win
c) two of the santaroos teams win
d) each of the santaroos teams win their particular final

[b^3]

For part b, look at what ways we can get only one winning. I.e. To satisfy what we're looking for we can have three situations.
A wins, B and C loses.
B wins, A and C loses.
C wins, A and B loses.
The sum of the probability of those events will give you the probability of only one winning.
So for the first one, the probability that B loses is one take the probability that B wins, so we have
.
Do that for all three and then add them up.

A similar situation goes for part c.
How can we have 2 teams winning?
A and B wins, C loses.
A and C wins, B loses.
B and C wins, A loses.

Hope that helps

EDIT: Also note that this works because each of the events are independent, since the teams are in separate divisions.