document.write( "Question 519221: How many ways can 7 students be assigned a seat in a classroom if there are 10 seats in a row? \n" ); document.write( "
Algebra.Com's Answer #345458 by Maths68(1474)\"\" \"About 
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First Student can be assigned a seat = 10 ways
\n" ); document.write( "Since the 1 seat is occupied next student has 9 seats to sit
\n" ); document.write( "Second Student can be assigned a seat = 9 ways
\n" ); document.write( "Since the 2 seats are occupied next student has 8 seats to sit
\n" ); document.write( "Third Student can be assigned a seat = 8 ways
\n" ); document.write( "Since the 3 seats are occupied next student has 7 seats to sit
\n" ); document.write( "Fourth Student can be assigned a seat = 7 ways
\n" ); document.write( "Since the 4 seats are occupied next student has 6 seats to sit
\n" ); document.write( "Fifth Student can be assigned a seat = 6 ways
\n" ); document.write( "Since the 5 seats are occupied next student has 5 seats to sit
\n" ); document.write( "Sixth Student can be assigned a seat = 5 ways
\n" ); document.write( "Since the 6 seats are occupied next student has 4 seats to sit
\n" ); document.write( "Seventh Student can be assigned a seat = 4 ways\r
\n" ); document.write( "\n" ); document.write( "7 students can be assigned a seat in a classroom =10*9*8*7*5*4=604800 ways \r
\n" ); document.write( "\n" ); document.write( "It is a case of choosing 7 out of 10
\n" ); document.write( "nPr=n!/(n-r)!
\n" ); document.write( "10P7=10!/(10-7)!
\n" ); document.write( "10P7=10!/3!
\n" ); document.write( "10P7=10*8*7*6*5*4*3!/3!
\n" ); document.write( "Cancel out 3!
\n" ); document.write( "10P7=10*9*8*7*6*5*4=604800 ways\r
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