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Need Help In Probability Please!!! (1 Viewer)

Nassoum

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3. There are 34 men and 32 women at a party. Of these, 13 men and 19 women are married. If 2 people are chosen at random, find the probability that:

(b) 1 will be a married woman and the other an unmarried man.

I did 19/66x21/65=133/1430 and i got this wrong.
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Lastly, 1. A bag contains 5 red. 6 blue, 2 white and 7 green balls. If 2 are selected at random (without replacement), find the probability of getting:

(b) A blue and a white ball

I got 6/20x2/19=3/95 and i got this wrong.
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10. To win a game of Lotto you need to choose the correct 6 numbers out of 44 numbers. Find the probability of winning first prize in Lotto, as a fraction in its simplest form.

I did 1 - (38/44x37/43)=243/946 but i got this wrong.
 
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P

pLuvia

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First one
19/32*21/34=399/1088

Second one
You are on the right track, but what if you get a white and blue ball? In that order?

6/20*2/19+2/20*6/19= that's the answer

Last one
What's the probability of choosing one of the numbers? 1/44
The second number now that one of the first numbers are gone? 1/43
....3rd? 4th? 5th?
The sixth number? 1/39

Multiply all of them and you should get the answer
 

karentao77

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LOLLLLL nassim.. o_O
how was the test?
dunno if u got the right answer yet.. but

3 (b) there are 2 probabilities for this one P(married woman, then unmarried man) + P(unmarried man, then married woman) = (19/66 x 21/65) + (21/66 x 19/65) = 133/715

1 (b) P(blue, then white) + P(white then blue) = (6/20 x 2/19) + (2/20 x 6/19) = 6/95

10. there are 6 at the start out of 44.. so
6/44 x 5/43 x 4/42 x 3/41 x 2/40 x 1/39 = 1/7059052
 
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