Probability
What is Probability?
Probability is the likelihood that something or an event will happen. To determine probability you must first determine how many possible results or outcomes there are. Once you find the outcomes it is easy to find the probability of something. You can even make predictions about what will happen based on what you already know. There are simple events and compound events.
How do you find all possible outcomes?
There a few different ways to calculate/determine the total possible outcomes. Of course you can write down all of the possibilities, but sometimes that method is just not practical and will take you a very long time. Tools to help calculate the total outcomes are a Tree Diagram and knowing the Counting Principle.
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Simple events are events that happen by themselves and well are simple. If you roll the dice you have a 1 out of six chance or probability of getting any of the 6 different numbers. If you flip a coin you only have 2 possible outcome. And if you have a bag of different colored marbles it's easy to compute the probability.
Using the Tree Diagram or Counting Principle
When you are faced with many options you can figure out all of the possible outcomes by using the tree diagram which is more of a visual and helps you know exactly what the outcomes are and the Counting Principle which just uses simple multiplication to quickly calculate all of the total outcomes. EXAMPLE: How many
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This is a simple tree diagram to show how to use one for flipping a coin. If you wanted to know all of the possible outcomes of flipping two coins, then there would be an additional set of branches to represent the 2nd coin toss.