1.5 Independent and Dependent Events

Flipping a Coin

Independent Event  Situations in which the occurrence or non- occurrence of one event has no influence on the probability of the other event occurring.

2 Aces in here

Dependent Events  The occurrence or non-occurrence of one event influences the probability of the other event occurring.

Independent or Dependent  Richards has a container with 5 people names in it. The first name he draws out gets first prize. The second name he draws out get second price.  Are these dependent or independent events?

Pencils  Olivia has four highlighting pens in her pencil case: two yellow, one orange, and one blue. She reaches into her pencil case and randomly chooses a highlighter. After she uses it, she immediately replaces it in the case so it can be used again. What is the probability that she will choose:  Two yellow highlighters?  A yellow highlighter followed by a blue highlighter?

Finding Probabilities of Compound Events  Answer the same questions from last slide using another method.

Multiplicative Principle for Independent Events

My New Game  Is my Game Fair?  Player A wins a point if a spinner lands on red AND an even number is rolled  Player B wins a point if the spinner lands on yellow or green and a composite number is rolled.

Drawing Cards  What is the probability of a King?  Two Aces and Two Kings are in my hand.

Conditional Probability  Probability of a second event occurring given that the first event occurred.

Multiplicative Principle for Dependent Events

Those Dang Telemarketers  How Much did the Telemarketer sell in 1000 calls?  The experiment probability of a call receiver staying on the line for at least a minute was 16%  The conditional probability of a call resulting in a sale, given that they receiver stayed on the line for more than a minute was 10%  No sales were made if the call hung up right away.

Assignment  Page 53 #’s 1-5, 7,11