please help (by tomorrow)

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maths_arghh234

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Ann is a tennis player
when she plays a match against Brenda she has probability 0.3 of winning
when she plays against Carol she has probability 0.4 of winning
when she plays against Debbie she has probability 0.6 of winning
Ann goes to the Tennis Club one morning and finds that Brenda, Carol and Debbie are all there waiting to play against her. Ann tosses 2 fair coins to decide her opponent.
If she obtains 2 heads she will play against Brenda.
If she obtains 2 tails she will play against Carol.
If she obtains 1 heads and 1 tail she will play against Debbie.

a) Find the probability that Ann wins her match.
b) Given that Ann wins her match find the probability that she played against Debbie.

i've asked a teacher during school today for help with it and he said to do a tree diagram, i tried and i don't know how to do one for this question. it's been ages since i learnt tree diagrams !!
i know how to do ( b) i am completely stumped on hpw to get the numbers and how to draw this tree diagram pleaasee hellp !!! thank :!: :)
 
Ann goes to the Tennis Club one morning and finds that Brenda, Carol and Debbie are all there waiting to play against her. Ann tosses 2 fair coins to decide her opponent.
If she obtains 2 heads she will play against Brenda.
If she obtains 2 tails she will play against Carol.
If she obtains 1 heads and 1 tail she will play against Debbie.

a) Find the probability that Ann wins her match.
b) Given that Ann wins her match find the probability that she played against Debbie.

i've asked a teacher during school today for help with it and he said to do a tree diagram, i tried and i don't know how to do one for this question. it's been ages since i learnt tree diagrams !!
i know how to do ( b) i am completely stumped on hpw to get the numbers and how to draw this tree diagram
Click to expand...

The tree diagram starts with three branches – one for each opponent. Since the odds of facing them are all equal, the probability along each path is 1/3, so write 1/3 beside each branch.

At the end of each branch, draw two more branches – one for a win and one for a loss. Write the appropriate probabilities of winning and losing each match (as stated in the problem) beside each branch.

Finally, multiply both numbers along each possible path (there are six) and write the answer at the end of each path.

Now, you do the rest. :)
 
maths_arghh234 said:
Ann is a tennis player
when she plays a match against Brenda she has probability 0.3 of winning
when she plays against Carol she has probability 0.4 of winning
when she plays against Debbie she has probability 0.6 of winning
Ann goes to the Tennis Club one morning and finds that Brenda, Carol and Debbie are all there waiting to play against her. Ann tosses 2 fair coins to decide her opponent.
If she obtains 2 heads she will play against Brenda.
If she obtains 2 tails she will play against Carol.
If she obtains 1 heads and 1 tail she will play against Debbie.

a) Find the probability that Ann wins her match.
b) Given that Ann wins her match find the probability that she played against Debbie.

i've asked a teacher during school today for help with it and he said to do a tree diagram, i tried and i don't know how to do one for this question. it's been ages since i learnt tree diagrams !!
i know how to do ( b) i am completely stumped on hpw to get the numbers and how to draw this tree diagram pleaasee hellp !!! thank :!: :)
Click to expand...

For a quick refresher on tree diagram go to:

http://www.onlinemathlearning.com/proba ... grams.html

To get more sites that discusses this topic - employ google.
 
wjm11 said:
Now, you do the rest. :)
Click to expand...

:D thank you!! that's just what i wanted :) .. i just seem to get stumped on how to get the numbers :\

and thanks for the website to.. i do employ google i just never seem to find a useful page ... i find the viruse ones lol :)
 
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