document.write( "Question 1005321: Four distinct letters are to be chosen from the set
\n" ); document.write( "{A, B, C, D, E, F, G, H}
\n" ); document.write( "Determine the number of ways to obtain a subset that includes each of the following
\n" ); document.write( "(1) the letter C
\n" ); document.write( "(2) both E and F
\n" ); document.write( "(3) either E or F, but not both \n" ); document.write( "

Algebra.Com's Answer #623319 by Edwin McCravy(20055) $\"\"$ $\"About$

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Four distinct letters are to be chosen from the set
\n" ); document.write( "{A, B, C, D, E, F, G, H}
\n" ); document.write( "Determine the number of ways to obtain a subset that includes each of the following
\n" ); document.write( "(1) the letter C
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document.write( "Choose the C 1 way and the other 3 from these 7 {A, B, D, E, F, G, H}\r\n" );
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document.write( "Answer 1*7C3 = 35 ways\r\n" );
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\n" ); document.write( "(2) both E and F
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document.write( "Choose them 1 way and choose the other 2 from these 6: {A, B, C, D, G, H}\r\n" );
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document.write( "Answer:  1*6C2 = 15 ways\r\n" );
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\n" ); document.write( "(3) either E or F, but not both
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document.write( "Case 1: Choose E 1 way and the other 3 from these 6 {A, B, C, D, G, H}\r\n" );
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document.write( "That's 1*6C3 = 20 ways\r\n" );
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document.write( "Case 2: Choose F 1 way and the other 3 from these 6 {A, B, C, D, G, H}\r\n" );
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document.write( "That's also 20 ways.\r\n" );
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document.write( "Answer: 20*2 = 40 ways.\r\n" );
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document.write( "Edwin

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