PROBABILITY

What is probability?

Probability is the measure of how an event is likely to occur out of the number of possible outcomes.

HOW DO WE DETERMINE PROBABILITY?

Probability =
Event
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Number of outcomes

EXAMPLES

• Rolling a dice and getting a 5(six sided). 1/6
• Flipping a coin to get heads. 1/2
• Winning the lottery jackpot. 1/A Billion
• Chance of rain in Texas in July. 1/30
• Copying a Picasso exactly correct. 1/500,000

WHY WE NEED PROBABILITY

• Figure out the odds of winning or losing
• The probability that you will land on Go in Monopoly
• The probability of winning a card game
• The probability that you will get struck out in baseball
• The probability of catching a Hail Mary pass

What is a complement?

A complement is all outcomes that are not the event.

EXAMPLES

• Rolling a dice and getting a 1, 2, 3, 4, or 6 5/6
• Flipping a coin and getting tails 1/2
• Winning a lesser prize or nothing (lottery)
• Chance of sunshine in Texas in July. 29/30
• Copying a Piccaso incorrectly. 499,999/500,000

WHAT IS THE DIFFERENCE BETWEEN THEORETICAL AND EXPERIMENTAL PROBABILITY?

Theoretical

What should happen after testing for probability.

Theoretically, if you flip a coin, you should get heads 5/10 times.

Untitled Slide

Experimental

What actually did happen after the testing for probability.

When you actually DO flip a coin, however, it's chance, so it could be 6/10 or 3/10 times on heads.

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