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What is the probability of rolling the sum of 5 or 8 on a pair of number cubes?

User Alex Maker
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2 Answers

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The probability of rolling a 5 is 4/36 (reduced to 1/9) and the probability of rolling an eight is 5/36. Rolling either would be 9/36 (reduced to 1/4)
User Justyn
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|\Omega|=6^2=36\\|A|=\underbrace{4}_{\text{the sum is 5}}+\underbrace{5}_{\text{the sum is 8}}=9\\\\P(A)=(9)/(36)=(1)/(4)=25\%

User Alvaro Pedraza
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