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#1 2006-03-13 11:19:01

4littlepiggiesmom
Member
Registered: 2006-01-09
Posts: 42

2 probablility questions

1. Suppose a fair coin is tossed 7 times. How many ways are there to get exactly three heads or three tails?   I got B

a. 7
b. 21
c. 35
d. 210
e. None of theese

2. Suppose three fair dice are thrown. What is the probabliity that the top faces will sum to 6?

a. 1
b. 1/6
c. 1/216
d. 5/108  MY ANSWER
e. Non of the these

Am I getting the right answer or do I need to redo it...again? K

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#2 2006-03-13 15:27:48

George,Y
Member
Registered: 2006-03-12
Posts: 1,306

Re: 2 probablility questions

c:  7 6 5/(3 2 1)=35
d:  right  (diceA diceB diceC) = (1 1 4), (1 4 1), (4 1 1), (1 2 3), (1 3 2), (2 1 3), (2 3 1), (3 1 2), (3 2 1), (2 2 2) ;Prob=(3+6+1)/(6 6 6)

Last edited by George,Y (2006-03-13 15:28:12)

X'(y-Xβ)=0

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#3 2006-03-13 16:46:56

4littlepiggiesmom
Member
Registered: 2006-01-09
Posts: 42

Thanks so much~

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#4 2006-03-13 17:01:52

George,Y
Member
Registered: 2006-03-12
Posts: 1,306

You r welcome

X'(y-Xβ)=0

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