document.write( "Question 658654: find the number of ways of selecting four letters from the word 'EXAMINATION'.ANSWER IS 136 PLS SOLVE THIS THANK U \n" ); document.write( "

Algebra.Com's Answer #410404 by MathLover1(20850) $\"\"$ $\"About$

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EXAMINATION has $\"11\"$ letters, and in which ' $\"A\"$ ', ' $\"I\"$ ' and ' $\"N\"$ ', all occur twice. $\"11C4\"$ , would have been fine if all letters were distinct.\r
\n" ); document.write( "\n" ); document.write( "So, we have $\"+E\"$ , $\"+X\"$ , $\"M\"$ , $\"T\"$ , $\"O\"$ , ( $\"AA\"$ ), ( $\"II\"$ ), ( $\"NN\"$ )... $\"8\"$ distinct letters.\r
\n" ); document.write( "\n" ); document.write( "1. $\"4\"$ letters selected, which are $\"all\"$ distinct: $\"8C4+=+70\"$
\n" ); document.write( "2. $\"2\"$ letters alike, and $\"2\"$ distinct (eg: $\"AAEX\"$ ) = $\"+3C1+%2A+7C2+=+63\"$
\n" ); document.write( "3. $\"2\"$ letters alike, and $\"2\"$ letters alike (eg: $\"AAII\"$ ) = $\"3C2+=+3\"$ \r
\n" ); document.write( "\n" ); document.write( "So answer is, $\"+70+%2B+63+%2B+3+=+136\"$ . \n" ); document.write( "

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