document.write( "Question 765931: Two light house flash their lights every 20 seconds and 30 seconds respectively. Given that they flashed together at 8:00 P.M.. When will they next flash together? \n" ); document.write( "

Algebra.Com's Answer #466576 by josmiceli(19441) $\"\"$ $\"About$

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Find the smallest number that both
\n" ); document.write( "20 and 30 divide into evenly
\n" ); document.write( " $\"+120+%2F+20+=+6+\"$
\n" ); document.write( " $\"+120+%2F+30+=+4+\"$
\n" ); document.write( "but,
\n" ); document.write( " $\"+60%2F20+=+3+\"$
\n" ); document.write( " $\"+60%2F30+=+2+\"$
\n" ); document.write( "--------------
\n" ); document.write( "In 60 seconds, or 8:01 PM, they both
\n" ); document.write( "flash together
\n" ); document.write( " \n" ); document.write( "

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