A tent is to be built in the form of a cylinder of radius 7 m surmounted by a cone of the same radius. If the height of the cylindrical part is 8 m and slant height of the conical part is 12 m, how much canvas will be required to build the tent? Allow 20% extra canvas for folding and stitching. (Take π = 22/7)

Radius of cone = Radius of cylinder = r = 7 m

Height of cylinder = h = 8 m

Slant height of cone = l = 12 m

Canvas required = Curved surface area of cylinder + Curved surface area of cone

= $$2 \pi r h + \pi r l = (\pi r) (2 h + l)$$

= $$(\frac{22}{7} \times 7) (2 \times 8 + 12)$$

= $$22 \times 28 = 616 m^2$$

Also, 20% extra canvas is required for folding and stitching

$$\therefore$$ Total canvas required = $$\frac{120}{100} \times 616 = 739.2 m^2$$