$\"\"$

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(a)

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The arithmetic series of the seat is $\"\"$ and $\"\"$

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Find the common difference $\"\"$ .

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$\"\"$ .

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Here $\"\"$ , $\"\"$ and $\"\"$ .

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Find $\"\"$ .

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The general form of $\"\"$ -terms of arithmetic series $\"\"$

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Substitute $\"\"$ , $\"\"$ and $\"\"$ in the general form.

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$\"\"$

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Substitute $\"\"$ , $\"\"$ and $\"\"$ in the general form.

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$\"\"$

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Find the $\"\"$ term.

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$\"\"$

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Substitute $\"\"$ and $\"\"$ in the general form.

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$\"\"$

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$\"\"$ .

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The arithmetic equation is $\"\"$

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$\"\"$

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(b)

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The total num of seats in the auditorium is

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The general form of partial sum of $\"\"$ -terms $\"\"$ .

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Substitute $\"\"$ , $\"\"$ and $\"\"$ in the general form.

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$\"\"$

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The total num of seats in the auditorium is $\"\"$

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$\"\"$

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(c)

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Second auditorium: $\"\"$ , $\"\"$ and $\"\"$ .

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Find $\"\"$ .

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The general form of $\"\"$ -terms of arthmetic series $\"\"$

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Substitute $\"\"$ , $\"\"$ and $\"\"$ in the general form.

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$\"\"$

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The general form of partial sum of $\"\"$ -terms $\"\"$ .

\

Substitute $\"\"$ , $\"\"$ and $\"\"$ in the general form.

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$\"\"$

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The total number of seats in the second auditorium is $\"\"$ .

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$\"\"$

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(a) The arthmetic equation is $\"\"$ .

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(b) The total num of seats in the auditorium is $\"\"$

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(c) The total num of seats in the auditorium is $\"\"$ .