Question

Calculate the cost of electricity for a house in which 6 bulbs of 60 watt each and 5 fans of 40 watt each are used for 10 hours a day for thirty days if the cost of each unit (kWh) is rs 1.05 .

Answer 1

Solution :- 6 bulbs of 60 watt each used for/hour consume.
6 × 60 = 360 Wh
When used for 10 hours consumption for each day
= 360 × 10
= 3600 Wh
5 fans of 40 watt each used for 1 hour consume
5 × 40 = 200 Wh
When used for 10 days hours consumption for each day = 200 × 10 = 2000 Wh
Tatal electricity consumed in 30 days
= 3600 × 30 + 2000 × 30
= ( 108000 + 60000 ) Wh
= 168000 Wh
= 168 kWh
Cost = 168 × 1.05
= rs 176.40