Question
A game consists of tossing three coins once and then
rolling two dice. Find the probability of getting all heads in the coin toss and a sum equal to 9 on the dice.Solution
For tossing 3 coins: Total number of possible outcomes = 23 = 8 Number of favourable outcomes = 1 (HHH) So, probability of getting all heads while tossing three coins = (1/8) For rolling 2 dice: Total number of possible outcomes = 6 × 6 = 36 Number of favourable outcomes = 4 [(3,6), (4,5), (5,4), (6,3)] So, Probability of getting a sum equal to 9 while rolling 2 dice = (4/36) = (1/9) Required probability = (1/8) × (1/9) = 1/72
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