A tent of height 77 dm is in the form a right circular cylinder of diameter 36 m and height 44 dm surmounted by a right circular cone. Find the cost of the canvas at Rs. 3.50 per m2. 
Height of tent =77dm
=7.7m
Radius of the cylinder 
=18 m
Height of cylinder =44dm =4.4m
Height of cone = (7.7-4.4) m
=3.3m
Curved Surface area of cylinder portion of the tent 
= 2 × (22/7) × 18 × 4.4
= 497.83 m2
Curved surface area of conical tent =π r l
Slant height of cone 
= 18.3m
Curved surface area of cone = (22/7) × 18 × 18.3
= 1035.26m2
Total surface area of the tent = 497.83m2 + 1035.26m2
= 1533.09m2
Total cost of canvas = 3.50 × 1533.09
= Rs 5365.82
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