Pranith recived an electric bill for the month of April. He started verifying it by calculating the electrical energy consumed by a 2000 W electrical appliance that is used for two hours every day in his workshop. In his house he used bulbs of 100 W for 4 hours every day in the month of april, which con-sumes the same electrical energy as that of the elec-trical appliance in the work shop. Find the number of bulbs Panith uses in his house.

Explanation

Electrical energy consumed by 1000 W appliance used for one hour is one unit. 2000 W appliance used for two hours consumes 4 units of electrical energy. In thirty days, the consumption is 120 units. Ten 100 W bulbs used for one hour consume for 1 unit of energy. If they are used for 4 hours, energy consumed = 4 units. In thirty days, they consume 120 units.