## Wednesday, May 16, 2007

### TranSCRIBIN'

Well today we had some different classes....

We started off with a Gizmo call to the Blogical Minds class in the US. Unfortunately I had completely forgot that this was going to happen in the hectic last couple of weeks so I did not have any questions prepared for them. But they had plenty for us :-). I must say that trying to answer something on the spot is brutally hard (These weren't easy questions either) so people, including me, were a little hesitant at times to respond. So that was a fun deviation from our usual routine.

But to the mathematics....

Easy mathematics :-)....

Well we all seemed to grok this probability thing. Today we learned to distinguish between dependent and independent events and how to calculate dependent event probabilities.

A dependent event is an event that the first event effects and and independent event is an event that does not depend on what happens in the first event. So we did a few questions to demonstrate this concept...

The only one event that effects the other event is the removal of the card without replacement because that changes the sample space.

Changes in sample is not the only way to cause dependency. If something within the sample space is changed it changes the odds of the events as shown in the next question.

When a marble is drawn it is replaced with a marble of the other color changing the odds and making this another dependent situation. We got the odds at the end of the probability tree by multiplying along the branches. Then to get a combined probability figure you add all the favorable outcomes.

As we saw with other questions this process generally works for calculating the odds of a singular/series of event(s) . We also found another way this relates to combinatorics in this class because Mr.K showed us that the questions can seem different but they will actually be the same like the flipping of the coin and the children. So this concept seems to be fairly simple but Mr. K will find a way to make this hard on the test. Which I hope will be soon so we can get a few days of review at the end of the year.

Auf Wiedersehen (See if answer tips can get that)