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The topic of this question is systems of linear equations.
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This question is about a broadway theater with 500 seats that has three types of seats.
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Its orchestra seats sell for $50 each.
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The main seats are $35 each, and the balcony seats are $25 each.
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Given that when all the seats are sold out, their revenue is $17.
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$11 ,100 and that when all the seats except for half of the orchestra seats are sold out, the revenue is $14 ,600, we want to find the number of orchestra, main, and balcony seats in this theater.
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Okay, so basically to start answering this question, we know we need to find the values of three numbers, that is the number of orchestra seats.
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The number of main seats, and the number of balcony seats.
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I've named those based on the names of the types of seats.
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And so we can call these three numbers r, m, and b.
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Those are the variable names.
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And to find their numerical values, we need three equations involving those variables to solve for.
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So first of all, one simple equation that we can get from the information is, from the total number of seats.
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So the number of orchestra seats plus the number of main and balcony seats is 500.
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And so simply put, the sum of our three values is 500.
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Now the sum of the sales from all these 500 seats is this number here.
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Now, how do we express that in terms of r, b, and m? well, we know that this is the number, this number is the total of sales from r seats, from m seats, and from b seats.
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So the total sales from r seats, that would be $50 per seat times r seats.
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That's $50 r dollars altogether.
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Similarly, the sales from the main seats is 35 times m, and the total sales from balcony seats is 25 times b.
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Now, if all the main and balcony seats are sold and half of the orchestra seats, we have this much.
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And so we still have the same amount of revenue from main and balcony seats, but this time we're only adding in half of the orchestra seats...