document.write( "Question 1193059: There is a box with a padlock You can open the box if you will be able to know the 4-digit code in the padlock. If the first digit of the 4-digit code is 5, how many possible codes are there if the repetition of the digit code is allowed?
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Algebra.Com's Answer #825012 by Theo(13342)\"\" \"About 
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there is one possible digit for the first position and 9 possible digits each for the next 3 digits.
\n" ); document.write( "the number of possible combinations is 1 * 9 * 9 * 9 = 9^3 = 729.
\n" ); document.write( "to understand how this works, assume there are only 2 possible digits for the next 3 positions.
\n" ); document.write( "the number of possible combinations would then be 1 * 2 * 2 * 2 = 2^3 = 8.
\n" ); document.write( "assuming the 2 possible numbers for each position were 2 and 3, then you would get:
\n" ); document.write( "5222
\n" ); document.write( "5223
\n" ); document.write( "5232
\n" ); document.write( "5233
\n" ); document.write( "5322
\n" ); document.write( "5323
\n" ); document.write( "5332
\n" ); document.write( "5333
\n" ); document.write( "the same concept applies when there are 9 possible numbers for each digit, except the number of combinations are too numerous to individually display.
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