Perimeter of a figure is explained here.
Perimeter is the total length of the boundary of a closed figure.
The perimeter of a simple closed figure is the sum of the measures of line-segments which have surrounded the figure.
Perimeter of ∆ABC = length (AB + BC + CA)
Perimeter of the quadrilateral DEKN = length (DE + EK + KN + ND)
Perimeter of the hexagon PQRSTU = length (PQ + QR + RS + ST + TU + UP)
The perimeter of a circle is the measure of its circumference. The perimeter of the circle of center O is its circumference.
Ken walks around a playground in his daily morning walk. How far does
he walk every morning? The playground is of the shape of a quadrilateral
having sides of length 112 m, 85 m, 69 m and 102 m.
Perimeter of the playground
= 112 m + 85 m + 69 m + 102 m
Ken walks 368 m around the playground, i.e. around the perimeter, every morning.