question_answer

  Calculate the electricity bill amount for a month of 30 days, if the following devices are used as specified (a) 3 bulbs of 50 W for 4 h (b) 2 tube lights of 40 W for 8 h (c) A TV of 100 W for 8 h (d) A refrigerator of 300 W for 24 h [Given, the cost of one unit is Rs. 3]

Answer:

                           (a) Energy consumed by 3 bulbs in one day   units   (b) Energy consumed by 2 tube lights in one day units  (c) Energy consumed by TV of 100 W for 8 h units (d) Energy consumed by refrigerator in one day units Total number of units consumed in 30 days = 30 x (0.6 + 0.64 + 0. 8 + 7.2) =30 x 9. 24 = 277. 2 units Cost of one unit = ` 3 Cost of 277.2 units = 3 x 277. 2 = ` 831.6.