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# Probability (for me, this question is tough) watch

1. I already knew how to do it. But can u tell me your method?

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2. (Original post by Elyn)
I already knew how to do it.
Then what was the point of this thread

But can u tell me your method?
There is only one method
3. Okay. Thank you

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4. Which method is used to answer this question ?

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5. (Original post by zed963)
Which method is used to answer this question ?
Can you do part (a)?
6. (Original post by TenOfThem)
Can you do part (a)?
Yes

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7. (Original post by zed963)
Yes
What did you get?
8. (Original post by TenOfThem)
What did you get?
5/22

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9. (Original post by Elyn)
It is ok.. I will ask others to teach me as communication problems.
Yup.. My first language is not english. I'm a chinese. Ppl here communicate using mandarin only.
I know my english is extremely bad. But at least i try . Sincerely, im sorry for the inconvenience and thanks for the comments. I will take it seriously.
For those who made a mock of me, please be polite to others, as it might hurt ppl. Everyone's IQ is different. Maybe some day they become better than u.. Who know?
(plz ignore my poor english) Thank you n hav a nice day ^^

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i think the question must have been lost in translation

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10. I Just tried solving this and got 25/99 which is well, near to 1/4 but not exact. This is what I did.

First I made a tree diagram for each family. For question a) I just did 1/3 * number of girls in family/total number of people in family for each of the 3 families and then added the 3 results up to get: 5/9

For question b) I just did 5/9 * 5/11 = 25/99

Anyone can tell me where I went wrong? Thanks
11. For part (b), that is probability of condition events, P(C/G).

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12. (Original post by zed963)
5/22

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How did you get that

The chance of a girl from family A is that is already greater than
13. (Original post by TenOfThem)
How did you get that

The chance of a girl from family A is that is already greater than
lol I don't know maybe in a year i'll tell you.
14. (Original post by zed963)
lol I don't know maybe in a year i'll tell you.
ok

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