Question 1034685
The cost of making 10 chairs is $340. The cost of making 22 chairs is $520.
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It's implied that there are some fixed costs.
(520 - 340)/(22-10) = 180/12 = $15 per chair
--> fixed costs of 340 - 10*15 = $190
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What is the cost per chair? 
$15, as shown above.
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Write a linear equation that tells you the total cost,
C, of making x chairs:
C = $190 + $15x
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If your total cost is $730, how many chairs did you make?
$730 - $190 = $540
$540/$15 = 36 chairs