is called the percentage error in x.

 The following formulae will be very useful in solving the problems.

Circle: If r is the radius, d is the diameter, P is the perimeter (circumference) and A is the area of a circle then        
           
Cube:  If x is the side, S is the surface area and V is the volume of a cube then     
                
Cone:  If 'r' is the base radius, 'h' is the height, 'l' is the slant height,   is the vertical angle,  is the semi-vertical angle, L is the lateral surface area, S is the total surface area and V is the volume of a (right circular) cone then
                            

Cylinder:  If r is the radius, h is the height, L is the lateral surface area, S is the total surface area and V is the volume of a (right circular) cylinder then   

Sphere:  If r is the radius, S is the surface area and V is the volume of a sphere then    

Simple pendulum:  If l is the length, T is the period of oscillation of a simple pendulum and y is the acceleration due to gravity, then    

Sector:  If r is the radius, l is the length of the arc and   is the angle,  p is the Perimeter and A is the area of a sector then