document.write( "Question 1090200: How many different four digit number can be written using the digits 1,2,3,4,5,6,7 and 8 only once such that the number 2 is contained once.
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Algebra.Com's Answer #704640 by Fombitz(32388)\"\" \"About 
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By contained once I assume you mean used once so the numbers would look like
\n" ); document.write( "2xyz, x2yz, xy2z, xyz2 where x,y,z are unique digits not equal to 2.
\n" ); document.write( "So then for each case,
\n" ); document.write( "\"N=7%2A6%2A5=210\"
\n" ); document.write( "There are 4 cases as shown so the total number of digits would be,
\n" ); document.write( "\"N%5Btot%5D=4%2A210\"
\n" ); document.write( "\"N%5Btot%5D=840\"
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