document.write( "Question 607052: a 40 row theater has 10 seats in the front row. the second row has 11 seats. if each row has one more than the row in front of it how many seats are there in the theater \n" ); document.write( "

Algebra.Com's Answer #382357 by josmiceli(19441) $\"\"$ $\"About$

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The rows are:
\n" ); document.write( " $\"+10+%2B+0+\"$
\n" ); document.write( " $\"+10+%2B+1+\"$
\n" ); document.write( " $\"+10+%2B+2+\"$
\n" ); document.write( " $\"+10+%2B+3+\"$
\n" ); document.write( "All the way to $\"+40+\"$ rows, so
\n" ); document.write( "This is the same as:
\n" ); document.write( " $\"+10%2A40+\"$ + 0 + 1 + 2 + 3 + ... + 39
\n" ); document.write( "This is $\"+400+\"$ + (1/2) x (total number of rows) x 39
\n" ); document.write( " $\"+400+%2B+%281%2F2%29%2A40%2A39+\"$
\n" ); document.write( " $\"+400+%2B+780+=+1180+\"$
\n" ); document.write( "There are 1180 seats
\n" ); document.write( " \n" ); document.write( "

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