2. JUST FLIPPING AROUND  Created By:  J. Whitlock, T.Garcia, and A. Aceves  For:  Ms. Wiltshire’s Class  On:  October 2002

3. Objective  Construct a sample space using a tree diagram to determine outcomes and describe the probability of real world events.

4. Probability Defined  The probability of an event is the ratio of the number of ways an event can occur to the number of possible outcomes.  Number of ways  P(event)= an event can occur  number of possible outcomes

5. The Problem  What is the probability of getting 2 heads when 2 coins are tossed?

6. Descriptions  A sample space can be used to determine probability.  A tree diagram can be used to create a sample space.

7. TREE DIAGRAM Step One-1 st coin  List all possible results of tossing one coin. Coin 1

8. TREE DIAGRAM Step Two-2 nd coin  List all possible outcomes for second coin next to each outcome of first coin Coin 1 Coin 2

9. Step Three Sample Space  Construct sample space Coin 1 Coin 2 (Possible outcomes) Sample Space

10. Explaining the solution  Count the number of items in the sample space-this is the possible outcomes (4)  Count the number of outcomes with 2 heads-this is the correct outcomes (1)  Write as a ratio: correct out of possible 1 out of 4

11. Explaining the solution (cont)  To change the ratio to a fraction, write the 1st number as the top and the 2nd number as the bottom. (1/4)

12. Explaining the solution (cont) To change the fraction to a percent:  divide  move the decimal 2 places and add a percent sign

13. Step 4 the solution The probability of tossing 2 heads is  1 out of 4 ¼¼  25% *HH* HT TH TT Sample Space

14. Works Cited Images and sounds collected from:  Microsoft Clipart Gallery I got the animated flipping coin from this site  100,000 Designer Clip Art

15. THE END Any Questions?