document.write( "Question 1133941: A box contains n balls marked from 1 to n.Two balls drawn in succession with replacement. Find the probability that number on the balls are consecutive integers(ignore the order of balls)?\r
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Algebra.Com's Answer #751552 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "The full space of all possible outcomes is (n x n) - matrix with  elements (events) that are equally likely.\r\n" );
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document.write( "Of these outcomes, the favorable are those that are one diagonal above or one diagonal below the major diagonal.\r\n" );
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document.write( "So, the number of favorable outcomes is 2*(n-1) against the total number of outcomes of .\r\n" );
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document.write( "Therefore, the answer is  , the same as in your post.\r\n" );
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document.write( "Thus your answer is correct.\r\n" );
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