Question 1196340
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An experiment of tossing a fair coin 5 times in a row has {{{2^5}}} = 32 possible different outcomes, in total (the space of events).


The favorable outcomes we are looking for are 2H of 5, or 3H of 5, or 5H of 5.


The number of outcomes 2H of 5 is  {{{C[5]^2}}} = {{{(5*4)/2}}} = 10.

The number of outcomes 3H of 5 is  {{{C[5]^3}}} = {{{(5*4)/(1*2)}}} = 10.

The number of outcomes 5H of 5 is  {{{C[5]^5}}} = 1.


So, the total number of favorable outcomes is  10+10+1 = 21.


Therefore, the desired probability is  P = {{{21/32}}}.    <U>ANSWER</U>
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Solved.