Two dice thrown together: What is the probability that neither die shows a 4 (i.e., the outcome on every die is not 4)?

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 = 25/36

Verification / 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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