Mensuration formulas Part-2

1.     Hexagon:

·        Area= 3a²√3/2

·        Perimeter= 6a

2.     Octagon:

·        Area= 2a²(1+√2)

·        Perimeter = 8a

3.     Circle:

·        Circumference= 2πr

·        Area of circle= πr²

·        π=22/7

4.     Semicircle:

·        Area= πr²/2

·        Perimeter= πr+2r

5.     Ring:

                     R= Outer circle

                     r= Inner circle

·        Area= π(R²-r²)

·        Perimeter:

Inner= 2πr

Outer= 2πR

6.     Sector:

                     L= length of arc

·        Length of an arc= 2πrθ/360°

·        Area of a sector= πr²θ/360°

7.     Middle Pathway in rectangle:

·        Area= (l+b-w)w

8.     Inner Pathway in rectangle:

·        Area= (l+b-2w)w

9.     Outer Pathway in rectangle:

·        Area= (l+b+2w)w

10.  kite:

·        Area= pq/2

·        Perimeter= 2(a+b)