What’s the probability…

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What’s the probability…
That this slideshow is about probability? By Ellen Brown, Kaylee Kline, and Madeline Zoe Hill McNichols

What is probability? Steps for solving probability problems:
1.) Determine all possibilities in a logical manner. Count them. 2.) Determine the number of these possibilities that are “favorable.” Thou shalt call these “winners.”

Example Problem If one of the four points is picked at random, what is the probability that the point lies on the angle? Solution! We follow the two basic steps by listing all possibilities and circle the winners.

Example Problem Suppose there are marbles. 10 marbles. In a pickle jar. If there are four red marbles and the rest are chartruse, what is the probability that when you reach into the pickle jar you will retrieve a red marble? number of red marbles 4 total marbles in jar = 2:5 therefore if I choose a marble from the pickle jar there is a 2:5 chance that I will choose a red marble

Example Problem Problem: If two of the four points are selected at random, the probability that they both lie on YW? W X Solution! We follow the two basic steps by listing all the possibilities in an orderly manner and circling the winners. If three of the six points lie on YW then the probability is 1:2. Z Y WX XY YZ WY XZ WZ

Practice Problem Two dice are thrown. What is the probability of getting two sixes?

SOLUTION! First we list the possibilities: 1,1 2,2 3,3 4,4 5,5 6,6
1,1 2,2 3,3 4,4 5,5 6,6 1,2 2,3 3,4 4,5 5,6 1,3 2,4 3,5 4,6 1,4 2,5 3,6 1,5 2,6 1,6 Now we circle the winner(s). There is only one winner in this problem therefore the answer is 1: 21.

Practice Problem There are six items in my pocket, half of the items are goats and half are kittens. If I take on item out of my pocket and put it on the table and then take out another item what is the probability that both of the items are goats?

SOLUTION! First we list the possibilities:
K1, K2 K2, K3 K3, G1 G1, G2 G2, G3 K1, K3 K2,G1 K3, G2 G1, G3 K1, G1 K2,G2 K3, G3 K1, G2, K2,G3 K1, G3 Then we circle the winner(s). There are three possibilities therefore there is a 3:15 chance that I will choose two goats which simplifies to 1:5.

Works Cited "The Math Forum at Drexel." Mathforum.org. Web. 17 Jan <http://mathforum.org/dr.math/faq/faq.prob.intro.html> "Expert Math Tutoring." Expertmathtutoring.com. Web. 17 Jan <http://www.expertmathtutoring.com/Probabilty-Knowledge-Examples.php>. Geometry for Enjoyment and Challenge. Evanston, Illinois : McDougal, Littell and Company, Print.