Question 1141562
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The probability in this case is the ratio (the fraction) whose numerator is equal to 90*4 = 360 seconds,


while the denominator is 3 hours (the time from 8 pm to 11 pm), which is 3*3600 seconds.


So, the probability under the question is  {{{360/(3*3600)}}} = {{{1/(3*10)}}} = {{{1/30}}}.


The answer is option B).
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