 Welcome guys again to another problem-solving session on quadrilateral. We are solving problems on angles and property of a quadrilateral And the given question says in a quadrilateral This is the quadrilateral abcd The angles abcnd are in the ratio 1 is to 2 is to 3 is to 4. So this is the vital information You have to find out the measure of each angle of the quadrilateral, right? So we have to find out measure of each angle of a quadrilateral So let's say this is the quadrilateral. So let's say abcnd This is this diagram should not be taken to scale because the angles are not in the ratio of 1 is to 2 is to 3 is to 4 This is just a representative diagram. So let's say These are the four angles of their quadrilateral and they are in the ratio of 1 is to 3 is to 4 So our solution will start like this. So we will say let let the angles of the given quadrilateral given quadrilateral b x b x b x 2x 3x and 4x, you know that whenever there is a problem related to ratios we You know take a variable x and then represent in The ratio as x 2x and 3x and 4x or whatever is the ratio given So basically if you see these four numbers are also in the same ratio x 2 1 is to 2 is to 3 is to 4 now How do we find x? So we know another information that some of the four angles that is x plus 2x plus 3x plus 4x This is equal to 360 degrees, isn't it? This is why I have to write angle some property of angles some property of a quadrilateral, so I am re-emphasizing you need to remember this and Always keep this in your mind that you'll have to use this particular property multiple number of times to solve problems on quadrilateral So x plus 2x plus 3x plus 4x is 360 degrees now rest is simply algebra So x plus 2x plus 3x plus 4x is nothing but 10x and This is equal to 360 degrees So dear friends x is equal to 36 degrees right? So x is now known So we can find out the other angles so hence the other angles would be so the angles are angles are x 2x 3x and 4x that is 36 degrees 72 degrees 108 degrees and 144 degrees so if you see the angles are 72 degrees that is 36 degrees that is x 72 72 degrees that is 2x 108 degrees that is 3x and 144 degrees which is 4x this is how we solve such problems