(I) ∆ABC is an isosceles triangle.
AB = AC = 5 cm, and BC = 1 cm.
∴ a = 5 cm, b = 5 cm, c = 1 cm.
∴ Perimeter = a + b + c
= 5 + 5 + 1 = 11 cm.
∴ Area(∆ABC) = 24.85 sq. cm.
(II) PBCS is a rectangle.
l = 6.5 cm, b = 1 cm.
Area of rectangle PBCS = l x× b
= 6.5 × 1 = 6.5 sq.cm.
(III) PQRS is a trapezium PT ⊥ QR
In Right angle ∆PTV,
(IV) Area of ADBE = Area of ∆FCG
∴ The total area of the paper used to make an aeroplane
= 2.485 + 6.5 + 1.29 + 4.5 + 4.5
= 19.275 sq. cm.