document.write( "Question 231924: How many multiples of 3 less than 1000 can be formed from the digits 2, 5, 9? \n" ); document.write( "
Algebra.Com's Answer #171500 by jsmallt9(3758)\"\" \"About 
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The keys to this problem are to understand that
  • Multiples of three are divisible by three.
  • Numbers are divisible by three if the sum of the digits of the number is divisible by three. For example, 104,652 is divisible by three becuase the digits add up to 18 (1+0+4+6+5+2 = 18) which is divisible by three.

\n" ); document.write( "So we a looking for numbers less than 1000 whose digits are 2, 5 or 9 and whose digits add up to a number divisible be 3.
\n" ); document.write( "
  • One digit numbers: 9:
  • Two digit numbers: 99
  • Three digit numbers: 222, 555, 999, 225, 252, 522

\n" ); document.write( "I don't think there are any others. \n" ); document.write( "
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