Question 588541
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Each switch in a system of six switches can be either on or off. A power surge randomly resets the six switches. 
What is the probability that this random setting for the system is one in which the first two switches are both 
in the on position?
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<pre>
For 6 switches, there are  {{{2^6}}}  possible positions/configurations.
It is the full (= total) space of events in this problem.


When 2 switches are in position "on", for the rest 6-2 = 4 switches there are  {{{2^4}}}  possible configurations.  
We call them "favorable configurations" in this problem.



The probability under the problem's question is

    P = {{{favorable/total}}} = {{{2^4/2^6}}} = {{{1/2^2}}} = {{{1/4}}} = 0.25.    <<<---===  <U>ANSWER</U>
</pre>

Solved.