document.write( "Question 304515: In the ordinary alphabet of 26-letters.\r
\n" ); document.write( "\n" ); document.write( "a) Define a \"4-letter word\" to be any list of 4 letters that contains at least one of the vowels A, E, I, O, U. How many 4-letter words are there?\r
\n" ); document.write( "\n" ); document.write( "b) Suppose, instead, we define a \"4-letter word\" to be any list of 4 letters that contains exactly one of the vowels A, E, I, O, U. How many 4-letter words are there?
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Algebra.Com's Answer #218029 by vleith(2983)\"\" \"About 
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Assume a four letter word
\n" ); document.write( "If the first letter is a vowel, then it can be 1 of 5 possible letters.
\n" ); document.write( "The remaining 3 letters in the word can be any of 26 letters. So
\n" ); document.write( "\"5%2A+26+%2A+26+%2A+26\" gives a word with the first letter as a vowel.
\n" ); document.write( "\"26%2A+5+%2A+26+%2A+26\" gives a word with the second letter as a vowel.
\n" ); document.write( "\"26+%2A+26+%2A+5+%2A+26\" gives a word with the third letter as a vowel.
\n" ); document.write( "\"26+%2A+26+%2A+26+%2A+5\" gives a word with the fourth letter as a vowel.
\n" ); document.write( "The total would be thge sum of those four products.\r
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\n" ); document.write( "\n" ); document.write( "B)
\n" ); document.write( "Part B is a misleading question. Does it mean there is a single vowel in the word or does it mean that multiple occurrences of the same vowel is allowed?
\n" ); document.write( "If a single vowel only is allowed then
\n" ); document.write( "If the first letter is a vowel, then it can be 1 of 5 possible letters.
\n" ); document.write( "The remaining 3 letters in the word can be any consonant letters. So
\n" ); document.write( "\"5%2A+21+%2A+21+%2A+21\" gives a word with the first letter as a vowel.
\n" ); document.write( "\"21%2A+5+%2A+21+%2A+21\" gives a word with the second letter as a vowel.
\n" ); document.write( "\"21+%2A+21+%2A+5+%2A+21\" gives a word with the third letter as a vowel.
\n" ); document.write( "\"21+%2A+21+%2A+21+%2A+5\" gives a word with the fourth letter as a vowel.
\n" ); document.write( "The total would be thge sum of those four products.\r
\n" ); document.write( "\n" ); document.write( "If you are allowed multiple occurrences of the same vowel, then change the 21 above to 22 (since you can have the same vowel again)\r
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