Difficulty: Easy
Correct Answer: 25/36
Explanation:
Introduction / Context:We seek the probability both dice avoid a particular face. With independence, multiply the single-die avoidance probability across the two dice.
Given Data / Assumptions:Each die: P(not 4) = 5/6; two independent dice.
Concept / Approach:P(neither shows 4) = (5/6) * (5/6) by independence.
Step-by-Step Solution:
P = (5/6)^2 = 25/36Verification / Alternative check:Complement: 1 − P(at least one 4) = 1 − [1 − (5/6)^2] = (5/6)^2 = 25/36.
Why Other Options Are Wrong:2/3 or 1/3 reflect single-die logic or complement misapplied; 17/36 is off by arithmetic.
Common Pitfalls:Using 1 − 2*(1/6) which double-counts the “both 4” case.
Final Answer:25/36
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