 Hi and welcome to the session. Today we will learn about conversion of units. We know that 1 meter is equal to 100 centimeters. Now let's see how much 1 meter square will be equal to in centimeters. Let us multiply 1 meter by 1 meter. This will be equal to 1 meter square. Now let us start with 1 meter square. So this will be equal to 1 meter into 1 meter. And 1 meter is equal to 100 centimeters. So let us replace 1 meter by 100 centimeters. So we will get 100 centimeters into 100 centimeters. And this will be equal to 10000 centimeters square. Thus 1 meter square is equal to 10000 centimeters square. From this we can also say that 1 centimeter square will be equal to 1 upon 10000 meters square. Now we generally measure the area of the land in hectares which is denoted by h a. And 1 hectare is equal to 10000 meters square. Now you can notice that when we convert a unit of area to a smaller unit that is when we converted 1 meter square to a smaller unit that is centimeter square. Then the resulting number of units is bigger that is here 10000 is bigger than 1. So when we convert a unit of area to a smaller unit then the resulting number of units is bigger. For example let us convert 5 meter square to centimeter square. So this will be equal to 5 into 10000 centimeters square which will be equal to 50000 centimeters square. Also when we convert a unit of area to a larger unit then the resulting number of units is smaller. For example let us convert 2000 millimeters square to centimeter square. So this will be equal to 2000 upon 100 centimeters square which will be equal to 20 centimeters square. Now here we have converted a unit of area that is 2000 millimeters square to a larger unit that is centimeter square. And thus the resulting number of units that is 20 is a smaller than 2000. Now we use conversion of units quite often in our day to day life. Whenever we go to some park or garden we see paths over there. Some surrounds the garden from all sides and some are cross paths in the garden. So now let us take an example to learn how to find the area of cross paths in a garden. We are given that a rectangle known 7 meters by 5 meters has two paths each 2 meter wide running through its middle one parallel to its length and another parallel to its width. Now we need to find the cost of constructing the paths at the rate of rupees 0.2 per centimeter square. Now to find out the cost of constructing the paths we need to find the area of these paths. So first of all we will find out the area of path A, B, C, D and then we will find the area of path E, F, G, H. You can see that the path P, Q, R, S is common to both the paths. That means to find the total area of the paths we will add the area of path A, B, C, D and area of path E, F, G, H and from that we will subtract the area of the path P, Q, R, S. So let us find area of paths which will be equal to area of path A, B, C, D and for this the length is 7 meters and width is 2 meters. So its area will be 7 into 2 meters square plus area of path E, F, G, H for this the length is 5 meters and width is 2 meters. So its area will be 5 into 2 meters square minus area of the square path P, Q, R, S. The side of this square path is 2 meters so its area will be 2 into 2 meters square which will be equal to 20 meters square. Now we need to find the cost of constructing the paths at the rate of rupees 0.2 per centimeter square. But the area is in meter square so that means first of all we need to convert this into centimeter square. Now we know that 1 meter square is equal to 10,000 centimeters square. So 20 meters square will be equal to 20 into 10,000 centimeters square which will be equal to 200,000 centimeters square. Now let us find out the cost of constructing the paths so this will be equal to rupees 0.2 into 200,000 which will be equal to rupees 14,000. Thus the cost of constructing the paths is rupees 14,000. With this we finished this session. Hope you must have understood all the concepts. Goodbye, take care and have a nice day.