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Question
The curved surface area of a frustum of a cone is πl (r1 + r2), where `l = sqrt(h^2 + (r_1 + r_2)^2)`, r1 and r2 are the radii of the two ends of the frustum and h is the vertical height.
Options
True
False
Solution
This statement is False.
Explanation:
We know that,
Curved surface area of frustum = πl(r1 + r2)
Where r1 and r2 are the radii of two ends (r1 > r2)
And l = slant height
`l = sqrt(h^2 + (r_1 + r_2)^2)` ...[In the statement, formula for calculating slant height is incorrect]
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