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Need Probability Help! (1 Viewer)

RHINO7

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I am having trouble with this question-

A game has a 2/5 probability of a win or a 3/8 probability of a draw.

If I play 2 of these games, find the probability of


i) a win and a draw-

ii) a loss and a draw-

iii) 2 wins-
 

Kujah

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If you take away the probability of a win and draw from 1, you'd get the probability of a loss.

Therefore, 1 - 2/5 - 3/8 = 9/40

You can use a tree diagram to plot two games out.

i) a win and a draw = 2/5 x 3/8 = 6/40 = 3/20

ii) a loss and a draw = 9/40 x 3/8 = 27/320

iii) 2 wins = 2/5 x 2/5 = 4/25

Correct my answers if I'm wrong ;)
 

pc4pc

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i'll make this quick i'm in a rush. you're confused that it didn't give you the probability of a loss. the sum of the probabilities of a W, L, D has to equal 1. use that, and draw a tree diagram.
 

RHINO7

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The answers are:


i)3/10

ii)27/160

iii)4/25
 
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RHINO7 said:
The answers are:


i)3/10

ii)27/160

iii)4/25
No they are not.

kujah said:
If you take away the probability of a win and draw from 1, you'd get the probability of a loss.

Therefore, 1 - 2/5 - 3/8 = 9/40

You can use a tree diagram to plot two games out.

i) a win and a draw = 2/5 x 3/8 = 6/40 = 3/20

ii) a loss and a draw = 9/40 x 3/8 = 27/320

iii) 2 wins = 2/5 x 2/5 = 4/25

Correct my answers if I'm wrong
Those are correct.
 

RHINO7

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Well now I know why I was getting the 'wrong' answer. The textbook must have misprints in the answer section.


THANKS
 

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