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प्रश्न
30 circular plates, each of radius 14 cm and thickness 3 cm are placed one above the another to form a cylindrical solid. Find volume of the cylinder so formed.
उत्तर
Given, radius of a circular plate, r = 14 cm
Thickness of a circular plate = 3 cm
Thickness of 30 circular plates = 30 × 3 = 90 cm
Since, 30 circular plates are placed one above the another to form a cylindrical solid.
Then, Height of the cylindrical solid, h = Thickness of 30 circular plates = 90 cm
Volume of the cylinder so formed = πr2h
= `(22/7) xx (14)^2 xx 90`
= `(22/7) xx 14 xx 14 xx 90`
= 22 × 28 × 90
= 55440 cm3
Hence, the volume of the cylinder so formed is 55440 cm3.
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