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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematical Methods CAS => Topic started by: GoodGuys on August 05, 2009, 07:56:22 pm

Title: help.. probability
Post by: GoodGuys on August 05, 2009, 07:56:22 pm

You have a jar which contains five white marbles, three red marbles, and two blue marbles. You draw two marbles, with replacement, from the jar. Let X be the number of red marbles drawn

a) What values can X take?
B) Draw up a table to show the probability distribution of X
C) cALCULATE THE PROBABILITY OF DRAWING EXACTLY ONE RED MARBLE  FROM THE JAR.
C) Calculate the probability of drawing at least one red marble from the jar.


It's seems so simple, yet i don't know why it can't pass through my mind.


Thanks :)

Title: Re: help.. probability
Post by: dcc on August 05, 2009, 08:19:40 pm

Start you off:

You are drawing two marbles.  The jar contains three red marbles.

X can clearly be 0, 1, 2.  That is, you can either end up with no red marbles, a single red marble or two red marbles.

Title: Re: help.. probability
Post by: GoodGuys on August 05, 2009, 08:23:07 pm

Quote from: dcc on August 05, 2009, 08:19:40 pm

Start you off:

You are drawing two marbles.  The jar contains three red marbles.

X can clearly be 0, 1, 2.  That is, you can either end up with no red marbles, a single red marble or two red marbles.

yeh i know answer A, however, i just couldnt figure out B.
thanks anyways