document.write( "Question 369915: The serial number on a $10 bill contains eight non-zero digits. If your $10 bill contains the digit 7 at least once, you win a prize. The probability that your $10 bill will be a prize-winning bill is:\r
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Algebra.Com's Answer #263647 by robertb(5830) $\"\"$ $\"About$

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Consider the complementary event of a 7 NOT appearing as a digit in the 8 digits. We then have 8 choices for filling 8 spaces. The probability that a 7 will not appear is then $\"8%5E8%2F9%5E8+=+%288%2F9%29%5E8\"$ , and the probability of a 7 appearing at least once is $\"1-%288%2F9%29%5E8+=+0.610255656\"$ . That is also the probability for a prize-winning bill. \n" ); document.write( "

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