Scribe post for March 10, 2009

Today in class we did more PROBABILITY.

Here are some of the exercises that we did during class:

a) Choose a student from grade 7 and choose a student from grade 8.

Are these choices DEPENDANTor INDEPENDENT on each other?
They are independent. Because the person you choose from grade 7 has no effect on the person you choose from grade 8. Therefore they are independent.

b) Choose one marble from a bag, then without replacing it, choose a second marble from the same bag.

Are these choices dependant or independent on each other? They are dependant because once you have chosen one marble from the bag, you have one less marble to chose from when you pick your second one. They have an effect on each other, therefore they dependant.

When figuring out if the choices you are making are dependant or independent on each other, the question you should as yourself is:DOES THE FIRST THING I DO, CHANGE THE SECOND THING I DO?

If the answer is YES, that means that they are DEPENDANT.
If the answer is NO, that means that they are INDEPENDENT.

HOMEWORK:
Make sure you know how to do a tree diagram, and a chart to find the sample space of probability problems.

Make sure that number of the day is finished: today's number was 7835.621

Don't forget TLE tomorrow!

(Please leave your comments and don't be afraid to point out any mistakes I have made so that next time I can do better!)

I choose Caitlin for the next scribepost. :)