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3 years ago

6

Consider a refrigerator that consumes 320 W of electric power when it is running. If the refrigerator runs only one quarterof th

e time and the unit cost of electricity is $0.09/kWh, the electricity cost of this refrigerator per month (30 days) is(a) $3.56 (b) 55.18 (a 53.54 {0159.26 [6) $20.74

1 answer:

ryzh [129]3 years ago

4 0

Answer:

$5.184

Explanation:

The cost can be calculated using the formula: $Cost = Load \ factor \times Number \ of \ hours \ \\M_{month} = M_{units} \times W\\$

Before using this, we require the following conversions:

<em>320 W → kW:</em>

$\frac {320}{1000} = 0.32$

<em>30 Days → Hours:</em>

$30 \times 24 = 720$

Using the above stated formula:

$M_{month} = 0.09 \times 0.32 \times \frac{1}{4} \times 720 = 5.184$

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