SOLUTION: the cost of electricity is $.08 for each of the first 300 kWh and $.13 for each kwh over 300 kwh. Find the number of Kilowhatt-hours used by a family that receaives a $51.95 electr

Algebra ->  Inequalities -> SOLUTION: the cost of electricity is $.08 for each of the first 300 kWh and $.13 for each kwh over 300 kwh. Find the number of Kilowhatt-hours used by a family that receaives a $51.95 electr      Log On


   

Question 534363: the cost of electricity is $.08 for each of the first 300 kWh and $.13 for each kwh over 300 kwh. Find the number of Kilowhatt-hours used by a family that receaives a $51.95 electric bill.
Found 2 solutions by josmiceli, stanbon:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let n = number of kWh used
given:
+51.95+=+.08%2A300+%2B+.13n+
+51.95+=+24+%2B+.13n+
+.13n+=+51.95+-+24+
+.13n+=+27.95+
+n+=+215+
They used 215 kWh

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The cost of electricity is $.08 for each of the first 300 kWh and $.13 for each kwh over 300 kwh. Find the number of Kilowhatt-hours used by a family that receives a $51.95 electric bill.
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cost = 0.08a + 0.13b
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51.95 = 0.08*300 + 0.13b
51.95 = 24.00 + 0.13b
0.13b = 27.95
b = 215 hrs
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Total hours = 215+300 = 515
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Cheers,
Stan H.
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