Modual 9 Flashcards
What are the four different rules of probability?
- p(event happening)
- p(even not occurring)
- p(A or B) = P(A) + P(B)
- p(A and B) = p(A) x p*=(B)
What should you never do if you get a fraction in probability?
simplify it
How can you find the probability of a event? e.g. i flip two fair cones, what is the probability of them both landing on tails?
Put it in a two way table
e.g. 1/4
What does mutually exclusive mean?
Can’t happen at the same time
Give a example of something that is mutually exclusive and something that isn’t
- Is = aces and kings. No comment interests
- Isn’t = Hearts and kings. You can get a king of hearts
What does collectively exhaustive events mean?
A set of events in probability
e.g. a six sided dice
What is a dependent event?
A event which depends on what happens before
e.g. if you have a bag of pens, every time you take a pen out, the probability changes
What is a independent event?
a event that is not affected by previous events
e.g. a coin, it does not remember that it landed on heads before and tails before that
What is the probability of a event happening?
total number of outcomes
Probely should always be given in which three different ways?
- a fraction
- a decimal
- a percentage
The first branch of the tree diagram is?
the choices
Going along tree digram is?
the sequence of events
The last branch of a tree diagram is?
First Branch X Second Branch
What is at the bottom right of the tree diagram?
The total column. Should always add up to 1
What is relative frequency?
all the outcomes
