document.write( "Question 1208684: Find the number of 7-digit positive integers, where the sum of the digits is divisible by 3. \n" ); document.write( "
Algebra.Com's Answer #847086 by math_tutor2020(3817)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "I have edited out the dollar signs from your question. \n" ); document.write( "It seems to be a strange copy/paste error.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The number 1,000,002 is the smallest 7-digit number where its digits add to 3. \n" ); document.write( "As such, that large number is a multiple of 3.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Then 1,000,002+3 = 1,000,005 is the next multiple of 3 and 1,000,005+3 = 1,000,008 is the next, and so on. \n" ); document.write( "This arithmetic sequence has common difference d = 3.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The nth term of this arithmetic sequence is \n" ); document.write( "an = 1,000,002 + 3(n-1)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The largest 7-digit multiple of 3 is 9,999,999. \n" ); document.write( "We don't have to add up the digits since 9 is a multiple of 3, sums of 9 will also get us a multiple of 3.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If you solved this equation \n" ); document.write( "9,999,999 = 1,000,002 + 3(n-1) \n" ); document.write( "then you would get the result n = 3,000,000 = 3 million \n" ); document.write( "I'll let the student handle the scratch work.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Answer: 3,000,000 aka 3 million \n" ); document.write( " \n" ); document.write( " |