A house has 3 tubelights, 2 fans and a television. Each tubelight draws 40W. The fan draws 80W and the television draws 60W. On an average, all the tubelights are kept ON for five hours, two fans for 12 hours each and the television for five hours a day. Find the cost of electric energy used in 30 days at the rate of Rs. 3.00 per KWH.
Total consumption of current in 30 days.
={(3 x 40 x 5) +(2 x 80 x 12) +(5 x 60 x 1)}30/100
= (600 +1,920 +30)30/100
= (2,820 x 30/1000) = 84.6 KWH
Cost of 1 unit (KWH) charge = 3
Cost of 84.6 KWH = 84.6 × 3 = Rs. 253.80
