Probability (but can you do this using combinations)

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The probability is 1/2 that a certain coin will turn up heads on any given toss. If teh coin is to be tossed three times, what is the probability that on at least one of the tosses the coin will turn up tails?

this is a basic probability problem and you can go about this by saying......... the probability of it being heads all three times is (1/2)^3 = 1/8

so the probability of it not being heads all three times (esentially tails once) is 1 - 1/8 = 7/8. That is the answer, but my question is there a way to do this using computations, i dont know if its late or what not....but my brain isnt functioning now, any help is Greatly Appreciated...
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by Morgoth » Fri Sep 26, 2008 2:12 am
Refer this

https://www.beatthegmat.com/coin-flip-qu ... 17911.html

With this strategy you can solve any coin flip question in less than 10 sec guaranteed!!!