MathDB
Random Three-Digit Number

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January 2, 2009
probability

Problem Statement

A base-10 10 three-digit number n n is selected at random. Which of the following is closest to the probability that the base-9 9 representation and the base-11 11 representation of n n are both three-digit numerals? <spanclass=′latex−bold′>(A)</span> 0.3<spanclass=′latex−bold′>(B)</span> 0.4<spanclass=′latex−bold′>(C)</span> 0.5<spanclass=′latex−bold′>(D)</span> 0.6<spanclass=′latex−bold′>(E)</span> 0.7 <span class='latex-bold'>(A)</span>\ 0.3 \qquad <span class='latex-bold'>(B)</span>\ 0.4 \qquad <span class='latex-bold'>(C)</span>\ 0.5 \qquad <span class='latex-bold'>(D)</span>\ 0.6 \qquad <span class='latex-bold'>(E)</span>\ 0.7
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