the radius and height of a cone are in the ratio 4:3 the area of basre is 154 cm find the areaof curved surface
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Good Question and Keep Progressing.
Here is your answer---
_______________________
Let the radius and Height of the cone be 4x and 3x respectively.
Given---
Area of the Base of the cone = 154 cm^2
pie × r^2 = 154
(22/7) × r^2 = 154
(4x)^2 = 154 × (7/22)
16 x^2 = 49
x^2 =49/16
x = √(49/16)
x = 7/4
Thus, Radius = 4x
= 4 × (7/4)
= 7 cm.
Height = 3x
= 3 × (7/4)
= 21/4 cm.
For the Slant Height(l),
Using the Formula,
(l)^2 = (r)^2 + (h)^2
(l)^2 = (7)^2 + (21/4)^2
(l)^2 = 49 + 27.5625
(l)^2 = 76.5625
l = √76.5625
l = 8.75
Using the Formula,
Curved Surface Area = pie × r × l
= (22/7) × 27 × 8.75
= 742.5 cm^2.
Thus, Curved Surface Area of the CONE is 742.5 cm^2.
_________________________
Hope it helps.
Please mark this answer as Brainliest.
Have a nice day.
Good Question and Keep Progressing.
Here is your answer---
_______________________
Let the radius and Height of the cone be 4x and 3x respectively.
Given---
Area of the Base of the cone = 154 cm^2
pie × r^2 = 154
(22/7) × r^2 = 154
(4x)^2 = 154 × (7/22)
16 x^2 = 49
x^2 =49/16
x = √(49/16)
x = 7/4
Thus, Radius = 4x
= 4 × (7/4)
= 7 cm.
Height = 3x
= 3 × (7/4)
= 21/4 cm.
For the Slant Height(l),
Using the Formula,
(l)^2 = (r)^2 + (h)^2
(l)^2 = (7)^2 + (21/4)^2
(l)^2 = 49 + 27.5625
(l)^2 = 76.5625
l = √76.5625
l = 8.75
Using the Formula,
Curved Surface Area = pie × r × l
= (22/7) × 27 × 8.75
= 742.5 cm^2.
Thus, Curved Surface Area of the CONE is 742.5 cm^2.
_________________________
Hope it helps.
Please mark this answer as Brainliest.
Have a nice day.
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