MAth Problem ??? Probability??? Help me, please ???  TOPIC_SOLVED

Sequences, counting (including probability), logic and truth tables, algorithms, number theory, set theory, etc.

MAth Problem ??? Probability??? Help me, please ???

Postby daivinhtran on Mon Mar 28, 2011 11:55 pm

1/ 2 heads or 2 tails appearing in 2 tosses of a coin.
2/ 3 heads or 2 tails appearing in 3 tosses of a coin.
3/ at least 2 heads appearing in 3 tosses of a coin.
4/ at least 3 heads appearing in 4 tosses of a coin.

-------------------------------------------------
And the probabability of obtaining 3 heads in 3 tosses of a coin??????? I tried it by myselfL
BUt I was so confused it.!! If I suppose like 1 event, then I have P=3/6 !!! (Because the outcomes is 6)
But if I suppose like 3 events, then I have P=(1/2) x (1/2) x (1/2)= 1/8
Which one is the correct answer??? Help me, please ???
daivinhtran
 
Posts: 4
Joined: Mon Mar 28, 2011 11:43 pm

Sponsor

Sponsor
 

Re: MAth Problem ??? Probability??? Help me, please ???  TOPIC_SOLVED

Postby Martingale on Sun Apr 03, 2011 4:57 am

daivinhtran wrote:1/ 2 heads or 2 tails appearing in 2 tosses of a coin.
2/ 3 heads or 2 tails appearing in 3 tosses of a coin.
3/ at least 2 heads appearing in 3 tosses of a coin.
4/ at least 3 heads appearing in 4 tosses of a coin.

-------------------------------------------------
And the probabability of obtaining 3 heads in 3 tosses of a coin??????? I tried it by myselfL
BUt I was so confused it.!! If I suppose like 1 event, then I have P=3/6 !!! (Because the outcomes is 6)
But if I suppose like 3 events, then I have P=(1/2) x (1/2) x (1/2)= 1/8
Which one is the correct answer??? Help me, please ???





provided the tosses are independent and the coin is fair.
User avatar
Martingale
 
Posts: 363
Joined: Mon Mar 30, 2009 1:30 pm
Location: USA


Return to Discrete Math