Probability

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Probabilty

Mutually Exclusive Events: Events that can not happen at the same time (Turn Left and Right at the same time)

Not Mutually Exclusive events: Events that can happen at the same time (Rain and I win a lottery)

Dependent : Probabilty for an event to occur doesn't affect the probabilty for the other effect occurring ( Raining today and Winning lottery) Wouldn't Get effected

Independent: Probabilty for an event to occur affects the probability for the second event to occur ( It is cold so it will snow today) Relation between events resulting one to have an effect on the other

Important

In probability "and" means multiply

In probability "or" means add

P= Probability

P(A and B) = (P multiply by A) Multiply (P multiply by B)

P(A or B) = (P multiply by A) Add (P multiply by B)

Compliment is (1-p)

Used to find the total outcome after used is stated

ECT: Probability to rain today 7/10

What is the probability for it not to rain today ?

3/10 or 30% or 0.3 *Can be Written as decimal or fraction or percentage *

This is "Compliment" = left over / total

Worked out using known number to find the unknown - How much needed to get to whole number

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Sample Space Diagram : Probability for two events happening together that {relate or opposite}

How to Draw Sample Space Diagrams ?

Put each of the events one on the horizontal and one on vertical (x=event 1 y= event 2)

Leave on space gap between the joining of them both on first row and column very beginning

1 st number on x add by 1st number on y and write outcome on block that joins them and continue with rest (1+1=2)

Calculate the digit of the sums (25 = 2-2-2-3-4-3-3-3-4-5-3-3-3-4-5-4-4-4-5-6-4-4-4-5-6)

Other way to (Step 4) multiply horizontal of sum digit by vertical 5*5=25

Look at what question is asking you

Probability exactly (6) just count how many times 6 is found in sum over total sum

Probability of number (less than 6) just count all numbers except 6 over total sum

Probability of number more then 6 = 0 just zero

Probability of 6 and less than 6 is 25/25

Probability of even 14/25 ; odd 10/25

Remember crocodile eats bigger number opens his mouth towards it

Leaves smaller number gives his back to it