document.write( "Question 901896: How many sets of 4-letter call letters are possible if:
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Algebra.Com's Answer #547091 by Fombitz(32388)\"\" \"About 
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Assuming the first two letters can be repeated.
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\n" ); document.write( "Assuming the first two letters cannot be repeated.
\n" ); document.write( "Last two repeated : \"N=26%2A25%2A26%2A26=439400\"
\n" ); document.write( "Last two not repeated : \"N=26%2A25%2A24%2A23=358800\"
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