Mrs. Bajracharya's house has 15A electricity meter. She uses 5 LED bulbs of 10 watt each for 4 hours, 2 televisions of 60 watt each for 5 hours and a refrigerator of 250
watt for 2 hours everyday. Find the cost of payment of the bill of a month at the rate
of Rs 4 per unit up to 20 units, Rs 7 per unit from 21 to 30 units and Rs 8.50 from 31
to 50 units with Rs 100 service charge, if the payment is made on 35th day of meter
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