You are Here: Home >< Maths

# GCSE Probability watch

1. Could anyone explain how to get to the answer for this question? I know the answer is 100% but could someone explain why it is 100%.
Attached Images

2. (Original post by gs--xa)
Could anyone explain how to get to the answer for this question? I know the answer is 100% but could someone explain why it is 100%.
Because it is entirely in A. Meaning that if C happens then most certainly A happens.
3. Since C is inside of A, the event C cant happen without the even A happening, hence if C happens then A happening has a probability of 1
4. (Original post by RDKGames)
Because it is entirely in A. Meaning that if C happens then most certainly A happens.
Since C is inside of A, the event C cant happen without the even A happening, hence if C happens then A happening has a probability of 1
Okay thanks that makes sense now

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: March 7, 2018
The home of Results and Clearing

### 2,939

people online now

### 1,567,000

students helped last year
Today on TSR

### University open days

1. Sheffield Hallam University
Tue, 21 Aug '18
2. Bournemouth University
Wed, 22 Aug '18
3. University of Buckingham
Thu, 23 Aug '18
Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams