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mensuration all formula |
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Answer» Rectangle : Area = lb Perimeter = 2(l+b) Square : Area = a×a Perimeter = 4a Parallelogram Area = l × h Perimeter = 2(l+b) Triangle : Area =b×h/2 or √s(s-a)(s-b)(s-c)…………….where s=a+b+c/2 Right angle Triangle : Area =1/2(bh) Perimeter = b+h+d Isosceles right angle triangle : Area = ½. a2 Perimeter = 2a+d……………………….where d=a√2 Equilateral Triangle : Area = √3. a2/4 or ½(ah)….where h = √3/2 Perimeter = 3a Trapezium : Area = 1/2h(a+b) Perimeter = Sum of all sides Rhombus : Area = d1 × d2/2 Perimeter = 4l Quadrilateral Area =1/2 × Diagonal × (Sum of offsets) Kite : Area = d1×d2/2 Perimeter = 2 × Sum on non-adjacent sides Circle : Area = πr^2 or πd^2/4 Circumference =2πr or πd Area of sector of a circle = (θπr^2 )/360 Frustum : Curved surface area = πh(r1+r2) Surface area= π( r12+ h(r1+r2) + r22) Cube : Volume: V = l3 Lateral surface area = 4a2 Surface Area: S = 6s2 Diagonal (d) = √3l Cuboid : Volume of cuboid: lbh Total surface area = 2 (lb + bh + hl) or 6l2 Length of diagonal =√(l^2+b^2+h^2) Right Circular Cylinder : Volume of Cylinder = π r2h Lateral Surface Area (LSA or CSA) = 2π r h Total Surface Area = TSA = 2 π r (r + h) Volume of hollow cylinder = π r h(R2– r2) Right Circular cone : Volume = 1/3 π r2h Curved surface area: CSA= π r l Total surface area = TSA = πr(r + l ) Sphere Volume: V = 4/3 πr3 Surface Area: S = 4πr2 Hemisphere : Volume = 2/3 π r3 Curved surface area(CSA) = 2 π r2 Total surface area = TSA = 3 π r2 Prism : Volume = Base area x h Lateral Surface area = perimeter of the base x h Pyramid: Volume of a right pyramid = (1/3) × area of the base × height. Area of the lateral faces of a right pyramid = (1/2) × perimeter of the base x slant height. Area of whole surface of a right pyramid = area of the lateral faces + area of the base. Tetrahedron : Area of its slant sides =3a2√3/4 Area of its whole surface = √3a2 Volume of the tetrahedron = (√2/12)a3 Regular Hexagon : Area = 3√3 a2/ 2 Perimeter = 6a Some other Formula : Area of Pathway running across the middle of a rectangle = w(l+b-w) Perimeter of Pathway around a rectangle field = 2(l+b+4w) Area of Pathway around a rectangle field =2w(l+b+2w) Perimeter of Pathway inside a rectangle field =2(l+b-4w) Area of Pathway inside a rectangle field =2w(l+b-2w) Area of four walls = 2h(l+ |
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