#1
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Coin tossing problem
Wouldn't mind a little help with this one. Got a test tomorrow and I don't really know how to do questions of this ilk. I have past papers but no answers [img]/images/graemlins/frown.gif[/img]
Here it is : The probability of obtaining a head when a certain coin is tossed is 0.4. The coin is tossed 10 times. Find the probability that there are exactly 3 heads and the third head occurs on the tenth toss. I can do the exactly 3 heads part, just not sure how to take into account the last coin being a head? Thanks. |
#2
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Re: Coin tossing problem
Just split the question into two parts:
1. Probability of getting 2 heads in 9 tosses 2. Probability of getting a head in a single toss (last toss) P(1) x P(2) = P(event) |
#3
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Re: Coin tossing problem
Ah, as easy as that? Cute. Thanks [img]/images/graemlins/smile.gif[/img]
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