An electric refrigerator rated `400 W` operates `8 hour//day`. What is the cost of the energy to operate it for `30` days at Rs. `3.00` per `kWh` ?

Explanation

The total energy consumed by the refrigerator in 30 days would be `400xx8.0 "hour/day"xx30"days"=96000 W h`
=96 KW h
Thus the cost of energy to operate the refregerator for 30 days is `096Kh h xxRs.3.00"per Kh h= Rs 288.00`