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| Question 1172900:  A party rental company has chairs and tables for rent. The total cost to rent 2 chairs and 5 tables is $33. The total cost to rent 8 chairs and 3 tables is $30. What is the cost to rent each chair and each table?
 Answer by greenestamps(13209)
      (Show Source): 
You can put this solution on YOUR website! 
 The first given rental is for 2 chairs and 5 tables, for a cost of $33.  The second is for 8 chairs and 3 tables, for a cost of $30.
 
 Observe that the second rental has 4 times as many chairs as the first.
 
 So imagine a third rental that is 4 times the first; it has 8 chairs and 20 tables, for a total of $132.
 
 Now the second and third rentals have the same numbers of chairs; the second had 3 tables and the third has 20 tables.  The difference in the number of tables is 17; and the difference in cost is $132-$30 = $102.  That means the cost of each table is $102/17 = $6.
 
 So the first rental of 2 chairs and 5 tables, for a cost of $33, includes 5($6) = $30 for the tables.  So the two chairs cost $3, and then each chair costs $1.50.
 
 ANSWERS: $6 for each table; $1.50 for each chair.
 
 A solution using formal algebra uses exactly the same calculations as the informal solution above.
 
 2c+5t = 33 (1)
 8c+3t = 30 (2)
 
 8c+20t = 132 (3) [(1), multiplied by 4]
 
 17t = 102  [the difference between (2) and (3)
 t = 6
 
 2c+5(6) = 33
 2c = 3
 c = 1.5
 
 
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