Question 372563
Work the problem backwards.
Find the probability that the coin will only land tails each time.
{{{P(H)=0.5}}}
{{{P(T)=0.5}}}
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{{{P(TTTT)=(0.5)(0.5)(0.5)(0.5)=0.0625}}}
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P(4 tails)+P(not 4 tails)=1
P(not 4 tails)=P(at least one head)=1-P(4 tails)
{{{P=1-0.0625}}}
{{{highlight(P=0.9375)}}}