document.write( "Question 1186206: The Greek theater has 50 seats in the first row. Each row behind the first-row gains 4 additional seats. How many seats are there in the 10th row? \n" ); document.write( "

Algebra.Com's Answer #817092 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Simply, you should add 9 times 4 seats to 50 seats\r\n" );
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document.write( "    the number of seats in 10th row = 50 + 4*9 = 50 + 36 = 86.\r\n" );
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document.write( "The sequence of numbers, presenting seats in each row is\r\n" );
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document.write( "    50. 54, 58, 62, . . . \r\n" );
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document.write( "each time you add 4 seats to the previous number.\r\n" );
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document.write( "It is so called arithmetic progression.\r\n" );
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document.write( "Its first term is 50.  Its common difference is 4.\r\n" );
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document.write( "The formula for the n-th term is   = .\r\n" );
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document.write( "For the 10th term (10th row) you have, according the formula,   = 50 + 4*(10-1) = 86,\r\n" );
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document.write( "exactly the same number as we obtained above.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved and explained.\r
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\n" ); document.write( "\n" ); document.write( "For introductory lessons on arithmetic progressions see \r
\n" ); document.write( "\n" ); document.write( "    - Arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - The proofs of the formulas for arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Problems on arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Arithmetic progressions\".\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-II
\n" ); document.write( "https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "into your archive and use when it is needed.\r
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