Given Information :-
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A cone with dimensions :-
- Radius = 3 cm
- Slant height ( l ) = 7 cm
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Another cone with dimensions :-
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- Radius = 5 cm
- Slant height = 9 cm
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To Find :-
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- The ratio of their total surface area
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Formula Used :-
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Solution :-
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For the first cone,
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Since, we don't really have to find the exact values of the surface area, we will let pi remain as a sign itself, this will make the calculations easier.
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Now, for the second cone,
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Now, we just have to calculate the ratio of their surface areas, thus,
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Thus, the ratio between the surface areas of the cones is 3 : 7.
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