Precalc probability 2014
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A. What is the chance that the sun will come up tomorrow? B. What is the chance that, while you are sleeping, your bed will C. turn to chocolate? D. What is the chance that it will rain today? E. What is the chance that the temperature will reach at least 70°F today? F. What is the chance that you will have homework tomorrow night? G. Come up with one of your own events. Algebra 2 Warm up 3.11.13 Directions: Place each event on the scale according to how likely it is to happen
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Transcript of Precalc probability 2014
A. What is the chance that the sun will come up tomorrow? B. What is the chance that, while you are sleeping, your bed will �C. turn to chocolate? D. What is the chance that it will rain today? �E. What is the chance that the temperature will reach at least 70°F �
today? F. What is the chance that you will have homework tomorrow
night?G. Come up with one of your own events.
Algebra 2 Warm up3.11.13
Directions: Place each event on the scale according to how likely it is to happen
Probability
The chance or likelihood of an event happening
A probability is a number between 0 and 1.0 = impossible1 = Certain
Who invented Probability?
PascalFermat
1600’s – Games of Chance
Theoretical vs. Experimental Probability
• Theoretical Probability - What we expect to happen based on mathematics.
• Experimental Probability – What actually does happen
The great number of times you perform an experiment, the closer the 2 become.
How do we calculate Theoretical Probability.
• Probability =
• Ex: Probability of getting HEADS in a coin toss.
Probability of getting the sum of 7 when rolling 2 dice:
Practice1. 2 dice are rolled.
a. Find the probability that the sum of the numbers is 10 b. The sum is at least 10
2. A letter is selected at random from the word TRIANGLE.a. Find the probability of selecting a vowelb. Find the probability of selecting a letter between F and Q.
Compliment
• The probability of an event NOT happening.• Remember the total probabilities add to 1.
Let P(A) = probability of event A
1 - P (A) = probability of event A NOT happening
Examples
2 possible scenarios
• 2 coins are tossed. Find the probability of:– A. Both showing heads– B. Both coins matching– C. There is at least one tails.
Example 2• A stack of 26 cards consists of the hearts and clubs only.
A card is randomly drawn. Find the probability that it is: A. A king B. A diamond C. A club D. A 7 or 8 E. A Red Ace
Example 2• A stack of 26 cards consists of the hearts and clubs only.
A card is randomly drawn. Find the probability that it is: A. A king B. A diamond C. A club D. A 7 or 8 E. A Red Ace
Without replacement.• A bag contains 2 purple, 3 green, and 4 blue marbles. 2 marbles are drawn at random. Find the probability of A. Both being green B. One is Green and one is Blue.
