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g you are shopping for a new refrigerator and the salesperson tells you get a better deal with the energy efficient model (because of more efficient compressor) even though it costs $1200 versus the standard model which costs $1005. Looking at the specifications, the energy efficient model uses 195 W whereas the standard uses 335 W. Also, because of better insulation. the energy efficient model runs 10% of the time versus the standard which runs 25% of the time. if electricity costs $0.12 per kWh, how long will it take to make up the difference in the cost?

User Johanne
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1 Answer

7 votes

Answer:

It will take 1996 hours (83 days) to make up the difference in price.

Step-by-step explanation:

Giving the following information:

Efficient model= 1200

Standard model= 1005

Price difference= $195

Efficient model= 195 Wh= 0.195Kwh (runs 10% of the time)

Standard model= 335Wh= 0.335Kwh (runs 25% of the time)

Electricity costs 0.12 an hour

Cost per hour:

Efficient model= (0.195Kwh*0.10)*0.12= 0.00234

Standard model= (0.335*0.25)*0.12= 0.10

Cost per hour difference= 0.10 - 0.00234= 0.0977

cost difference= cost per hour* number of hours

195= 0.0977*X

1996= X

It will take 1996 hours (83 days) to make up the difference in price.

User Kineolyan
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