posted by Aleah on .
This is a confusing problem to me also, can someone please help me?
What are the odds in favor of getting at least one head in three successive flips of a coin?
Pr(three heads)= 1/2*1/2*1/2
Pr(one head in three flips)= Pr(HTT)+Pr(HHT) + Pr(HHH)+ Pr(THT)+Pr(TTH)+ Pr(THH)+Pr(HTH)
= oddly enough 1/2*1/2*1/2 * 7
check me to make certain I included all the ways to get at least one head.
think on that one.
One comment. On the at least on head in three flips should equal the 1-Pr(no heads)0r 1=Pr(TTT) or 1-1/2*1/2*1/2= 7/8
post that same question in the little jiskha box search, and you'll find what you need.