Question 469918
A coin is flipped twice. What is the probability that one head and one tail will occur?

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P[(head 1st AND tail 2nd) OR (tail 1st AND head 2nd)]

AND means to multiply probabilities and OR means to ADD probabilities

P(heads 1st)×P(tails 2nd) + P(tails 1st)×P(heads 2nd)


All the probabilities are {{{1/2}}}, so

{{{1/2}}}×{{{1/2}}} + {{{1/2}}}×{{{1/2}}} = {{{1/4}}} + {{{1/4}}} = {{{2/4}}} = {{{1/2}}}

Edwin</pre>