document.write( "Question 1195856: If 321n=232seven find n\r
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Algebra.Com's Answer #828439 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "The problem is this:

\n" ); document.write( "321 (base n) = 232 (base 7)

\n" ); document.write( "Informally....

\n" ); document.write( "In any base (where the numbers are defined), 321 is greater than 232; so if 321 (base n) is equal to 232 (base 7), then the base n must be less than 7.

\n" ); document.write( "So try n=6....

\n" ); document.write( "321 (base 6)
\n" ); document.write( "3*6=18; 18+2=20
\n" ); document.write( "20*6=120; 120+1=121

\n" ); document.write( "232 (base 7)
\n" ); document.write( "2*7=14; 14+3=17
\n" ); document.write( "17*7=119; 119+2=121

\n" ); document.write( "n=6 works!

\n" ); document.write( "ANSWER: n=6

\n" ); document.write( "Formally....

\n" ); document.write( "321 (base n) = 3n^2+2n+1
\n" ); document.write( "232 (base 7) = 2(7^2)+3(7)+2 = 98+21+2 = 121

\n" ); document.write( "3n^2+2n+1=121
\n" ); document.write( "3n^2+2n-120 = 0
\n" ); document.write( "(n-6)(3n+20) = 0

\n" ); document.write( "n=6 or n=-20/3

\n" ); document.write( "Obviously the negative fractional answer makes not sense. So

\n" ); document.write( "ANSWER: n=6

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