Solution X is a number whose values are defined on the outcomes of a random
experiment Therefore, X is a random variable Now, sample space of the experiment is
S = {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT}
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PROBABILITY      559
Then
X (HHH) = Rs (2 × 3) = Rs 6
X(HHT) = X (HTH) = X(THH) = Rs (2 × 2 − 1 × 1 50) = Rs 2