Exercise · ZW-CLASSICAL-PROBABILITY-003 · ★☆☆ Basic
Two fair dice are rolled. What is the probability that the sum is 7?
Choose one option.
Show answer
- D. \(\frac{1}{6}\)
Explanation
Of the 36 ordered pairs, 6 add up to 7: \((1,6),(2,5),(3,4),(4,3),(5,2),(6,1)\). So \(\frac{6}{36}=\frac16\).
Review the concept: Classical probability
The classical probability \(P(A)\) of an event \(A\), when the sample space \(\Omega\) is finite with equally likely outcomes, is the ratio of favorable to possible outcomes.
\[P(A)=\frac{|A|}{|\Omega|}\]
More practice problems: classical probability
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- ZW-CLASSICAL-PROBABILITY-006 Two fair dice are rolled. What is the probability that the sum is at least 9?
- ZW-CLASSICAL-PROBABILITY-007 Two fair dice are rolled. What is the probability of getting at least one 6?
- ZW-CLASSICAL-PROBABILITY-008 Two cards are drawn at random, without replacement, from a 52-card deck. What is the probability th…
- ZW-CLASSICAL-PROBABILITY-009 Two fair coins are tossed and someone reasons with Omega=\0,1,2\ heads: “P(one head)=13”. What is t…
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