 Hi and welcome to the session I am Deepika here. Let's discuss the question if the radius of a sphere is measured as 9 meter with an error of 0.03 meter then find the approximate error in calculating its surface area. So let's start the solution. Given radius of sphere is equal to 9 meter that is delta r that is delta r is equal to 0.03 meter that as to the surface area of a sphere with radius r therefore s is equal to 4 pi r square this implies ds by dr is equal to 8 pi r that the approximate error in calculating the surface area is delta s therefore delta s is equal to ds by dr into delta r now ds by dr is 8 pi r this is equal to 8 pi r into delta r that is error in radius is 0.03 meter now put r is equal to 9 meter we have delta s is equal to 8 pi into 9 into 0.03 and this is equal to 2.16 pi meter square hence the approximate error in calculating the surface area is 2.16 pi meter square and this is our answer. I hope the question is clear to you. Bye and take care.