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प्रश्न
The base circumferences of two cones are the same. If their slant heights are in the ratio 5 : 4, find the ratio of their curved surface areas.
उत्तर
The base circumferences of the cones are equal, therefore the radius of base are equal.
Let radius be r.
Ratio between slant heights= 5:4
Let slant height of first cone = 5x and of second cone = 4x
Curved surface area of cone = `pirl` (where l = slant height)
Ratio of curved surface areas = `(pir xx 5x)/(pir xx 4x)`
= `5/4`
Ratio of curved surface areas = 5:4
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