document.write( "Question 145215This question is from textbook
\n" ); document.write( ": Help! Please-Thanks\r
\n" ); document.write( "\n" ); document.write( "13. (4 pts) At an annual flower show, 6 different entries are to be arranged in a row.
\n" ); document.write( "a) How many different arrangements of the entries are possible? 6!
\n" ); document.write( "b) If the owners of the 1st, 2nd, and 3rd place entries will be awarded prizes of $100, $50, and $25 respectively, how many ways can the prizes be awarded? 6 items taken 3 at a time 6*5*4 = 120 ???
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Algebra.Com's Answer #105890 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
a)\"6%2A5%2A4%2A3%2A2%2A1+=+720\"
\n" ); document.write( "b) You're looking for combinations here, not arrangements, because
\n" ); document.write( "you don't care how the prize winners are arranged, once they have
\n" ); document.write( "their prizes. You need the formula for combinations of 3 things
\n" ); document.write( "chosen from 6
\n" ); document.write( "\"6%21+%2F+%283%21+%2A%286-3%29%21%29+=+20\"
\n" ); document.write( "It's easy to check:
\n" ); document.write( "Call the entries ABCDEF
\n" ); document.write( "The possible combinations:
\n" ); document.write( "Including A
\n" ); document.write( "ABC ACD ADE AEF
\n" ); document.write( "ABD ACE ADF
\n" ); document.write( "ABE ACF
\n" ); document.write( "ABF
\n" ); document.write( "Including B (without repeats)
\n" ); document.write( "BCD BDE BEF
\n" ); document.write( "BCE BDF
\n" ); document.write( "BCF
\n" ); document.write( "Including C (without repeats)
\n" ); document.write( "CDE CEF
\n" ); document.write( "CDF
\n" ); document.write( "Including D (without repeats)
\n" ); document.write( "DEF
\n" ); document.write( "(Note that E and F are already combined with A,B,C,and D)
\n" ); document.write( "----------------------------
\n" ); document.write( "These add up to \"20\" combinations
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