document.write( "Question 508959: How many different 4-letter radio call letters can be made using the 26 capital letters of the English alphabet (Examples: WJBR, KDKA, WSTW) if the first letter must be K or W and no letter may be repeated. \n" ); document.write( "

Algebra.Com's Answer #341190 by oberobic(2304) $\"\"$ $\"About$

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The first letter has 2 possibilities: K and W.
\n" ); document.write( "The second letter has 24 possibilities given you cannot reuse K or W.
\n" ); document.write( "Once you take that letter, then the third letter has only 23 possibilities.
\n" ); document.write( "After you pick the third letter, then you only 22 choices for the last letter.
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\n" ); document.write( "2*24*23*22 = 24288
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\n" ); document.write( "BUT in your example you showed WSTW, which suggests the K and the W can be repeated as one of the other three letters. In turn, that means your total patterns are:
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\n" ); document.write( "2*26*25*24 = 31200
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\n" ); document.write( "Done. \n" ); document.write( "

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