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प्रश्न
The radius (in cm) of the largest right circular cone that can be cut out from a cube of edge 4.2 cm is
विकल्प
A. 4.2
B. 2.1
C. 8.4
D. 1.05
उत्तर
The height and diameter of the base of the largest right circular cone that can be cut out from a cube are equal to the edge of the cube.
Let the radius of the cone be r cm.
∴ 2r = 4.2 cm
`rArr r=4.2/2 cm =2.1 cm`
The correct answer is B
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