# Thread: Simple probability (sample space) - blur 4

1. ## Simple probability (sample space) - blur 4

hehehe..still have problem on this topic.. hope some body can help ..
tq for time

i already have the answer for a & b. i just stuck on c. the ans for c is 0.

2. The only reason I can see why the probability is zero is that students can only belong to one group...

3. Originally Posted by Gusbob
The only reason I can see why the probability is zero is that students can only belong to one group...
it mean because only one person select in this case at one time not 2 person. so question c mean
n(Scouts and Guides) = 0

4. What I meant was for that answer to be true, we have to assume that each student can only join 1 group.

5. Originally Posted by Gusbob
What I meant was for that answer to be true, we have to assume that each student can only join 1 group.
so it mean no selection for Both Scouts and Guides is select in this case???

6. Originally Posted by nikk
hehehe..still have problem on this topic.. hope some body can help ..
tq for time

i already have the answer for a & b. i just stuck on c. the ans for c is 0.
To calculate the probabilities you need to know the total number of students.

With the information you present the only assumption that appears appropriate is that every student belongs to one of the organisations, and that no student belongs to more than one.

With these assumptions the answer for c is zero because no student belongs to two organisations.

RonL