Question

Radius of the base of a cylindrical water drum open at the top is 35 CM and height 1.3m .Find the inner surface area of the water drum.

Answer 1

Hello...
Answer...

radius = r = 35cm
height = h = 1.3m = 130 cm

Inner surface area of water drum
= curved surface area + base area

= 2πrh + πr²

= πr (2h + r )

= 22/7×35×(2×130+35) cm²

= 32450cm²



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Answer 2

Radius of Base = 35 cm

Height = 1.3 m = 130 cm

Inner Surface Area = Curved Surface Area + Area of base

= 2 pi r h + pi r^2

= 2 × 22 × 35 × 130 / 7 + 22 × 35× 35 / 7

= 2 × 22× 5 × 130 + 22× 5 × 35 cm^2

= 220 × 130 + 110 × 35 cm^2

= 28600 + 3850 cm^2

= 32450 cm^2