Question

a man uses 100 watt bulb 8 hours a day and an electric heater of 300 watt for 4 hours a day .the total cost for month of November at the rate of 4 rupees per unit will be​

Answer 1

Answer:

Rs 240

Step-by-step explanation:

Given a man uses 100 watt bulb 8 hours a day and an electric heater of 300 watt for 4 hours a day .the total cost for month of November at the rate of 4 rupees per unit will be​

So energy consumed by 100 w bulb for 8 hours will be 800 watt

energy consumed by 300 w bulb for 4 hours will be 1200 watt

Now power will be 800 + 1200

                             = 2000 watt

                            = 2 K W

Now total units consumed N = 2 x 30 (because Nov has 30 days)

                      N = 60 units

Now rate per unit is Rs 4

So total cost for month of Nov will be 60 x 4 = Rs 240

Answer 2

Answer:

240

Step-by-step explanation:

bulb = 100 w = 0.1 kw

heater = 300 w = 0.3 kw

energy produce by both = (0.1x8) + (0.3x4) = 2kwh

cost per unit = 4rs

total cost for november = 30(2x4) = rs 240