Name Learning Tool 12 Date Probability, Let’s Try and See Probability, let’s try and see, if the outcome is what we think it will be. In any event, there will always be some favorable outcomes. There are 3 black marbles, 5 blue, 2 green. Let’s use theoretical probability. How likely am I, to pull out a black marble, when I reach into my marble bag? The formula for probability of an event, tells us the answer is 30 percent. But there’s another method, for us to see, experimental probability. Choose a marble, put it back. Do this 10 times and with a pencil, keep track of how many times the one you chose was black. Put this number over 10, and convert the fraction to percent. Learning Tools LT12 Grade 6, Ratios, Let’s Try and See Copyright © Houghton Mifflin Company. All rights reserved. 73746_C1-14_LT_Cln1 12 7/18/07 5:13:36 PM