Independent Probability
Independent probability – one event DOES NOT affect the outcome of the other.
This woman is not dependent on anyone else to survive, she will never catch influenza (influence).
Independent probability - NOT Influenced
Example 1
A bag contains 6 marbles, four red and two yellow. A marble is taken from the bag, its colour written down then it is returned to the bag. A marble is again taken from the bag, and its colour written down.
1. What is the probability of getting two red marbles?
2. And what is the probability of getting a red and a yellow marble?
Start by drawing a probability tree:
This can be redrawn as:
This is the probability tree for this example.
Add these up to check they equal 1 `16/36+8/36+8/36+4/36=(16+8+8+4)/36=36/36=1`
I. Therefore from the diagram above the probability of getting two red marbles is:
Red, Red =`16/36=8/18=4/9`
Probability of two reds is 4 in 9 or = 0.44 And if 1 = 100% then 0.44 = 44% chance.
II. What is the probability of getting a red and a yellow marble?
Add
`8/36+8/36=(8+8)/36=16/36=8/18=4/9`
The probability of getting a red and a yellow marble is 4 in 9 or = 0.44.
And if 1 = 100% then 0.44 = 44% chance.



