Year 9 probability T.T (1 Viewer)

HyperComplexxx

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There are 100 blue tickets and 100 red tickets sold in raffle; there are three prizes. Tickets are drawn without replacement.

i. Draw a tree diagram

I'm having trouble /facepalm
 

annagurl

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Bro, it's going to take forevers to do the tree
 

Omnipotence

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Draw a tree, red/blue and subsequent branches from each with red/blue then do it once more. For every branch write the fraction.
 

Omnipotence

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Its straightforward, look at a textbook or something...
The question doesn't belong in 3U section anyway.
 

xV1P3R

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Draw a tree, red/blue and subsequent branches from each with red/blue then do it once more. For every branch write the fraction.
This.

Start with red blue (showing chance of drawing red as winning or blue as winning). At the end of each branch, draw a new set of red/blue. You have in total 3 groups of branches representing the 3 prizes. Fractions at start would be 1/100, 1/100, changing to 1/99 or staying at 1/100 depending on what was drawn.

it would literally take me like 1minute to do it, but its not worth the paper and time if I got completely ignored and unappreciated last year.
Yet you spent more than a minute typing this to again be unappreciated?
 

Amogh

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http://i54.tinypic.com/25qq81u.jpg

As in the diagram, for the first pick it can either be red or blue. For the second pick it can either be red or blue, and the same for the third.

Now, for working out the fraction of probablity, simply look at the number of favoured outcomes and divide it by the total number in the sample space.
In the first pick, the probablity of picking a red raffle is 100/200 = 1/2 and the probability of picking a blue raffle is the same. On the other hand, AFTER having picked a red raffle, the probablity of picking another red raffle is 99/199 (Because a red raffle has been picked out, and 199 total raffles remain)

Use similar logic to work out each fraction.
Hope that helps!
 

pony_magician

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Wait. I started drawing it up, and now I feel dumb.

Do the colours even matter?
 

xV1P3R

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Colours are probably what we have to work out in later parts of the question. Like 3 red winners, 2 red 1 blue, or whatever
 

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