Jake is comparing the prices of two mattress cleaning companies. Company A charges $30 per mattress and an additional $13 as service charges. Company B charges $28 per mattress and an additional $15 as service charges.

Part A: Write an equation to represent each company's total charges for cleaning a certain number of mattresses. For both equations (one for Company A and one for Company B), define the variable used. (4 points)

Part B: Which company would charge less for cleaning 4 mattresses? Justify your answer. (3 points)

Part C: How much money is saved by using the services of Company B instead of Company A to clean 7 mattresses? (3 points)

company A : 13 + 30m.....where m = # of mattresses
company B : 15 + 28m.....where m = # of mattresses
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company A : cleaning 4 mattresses : 13 + 30(4) = 13 + 120 = 133
company B: cleaning 4 mattresses : 15 + 28(4) = 15 + 112 = 127
so company B would charge less
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company A : cleaning 7 mattresses : 13 + 30(7) = 223
company B: cleaning 7 mattresses: 15 + 28(7) = 211
so by using company B, u would save : 223 - 211 = $ 12