SOLUTION: 1
a sector of circle radius 7cm subtending an angle of 270° at the center of the circle,is used to form cone.
a:find the base radius of the cone.
b:calculate the area of the ba
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-> SOLUTION: 1
a sector of circle radius 7cm subtending an angle of 270° at the center of the circle,is used to form cone.
a:find the base radius of the cone.
b:calculate the area of the ba
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Question 1027471: 1
a sector of circle radius 7cm subtending an angle of 270° at the center of the circle,is used to form cone.
a:find the base radius of the cone.
b:calculate the area of the base of the cone correct to the nearest square centimetres. ( take π=22/7).
You can put this solution on YOUR website! Hi there,
Angle/360 = Length of arc/Pi x diameter.
270/360 = Length of arc/Pi x 14
Length of arc = (270 x Pi x 14)/360
Length of arc = 32.99cm.(2 decimal places)
When the sector is folded into a cone
the arc length becomes the cone's
circumference.
Circumference = Pi x diameter.
32.99 = Pi x diameter.
Diameter = 32.99/Pi
Diameter = 10.5cm
Diameter = 2 x radius
Radius = Diameter/2
Radius = 10.5/2
Radius = 5.25cm
b) Area of base of cone = Pi x radius^2
Area = Pi x 5.25^2
Area = 86.59cm^2
Area = 87cm^2 (nearest whole square centimetre)
Hope this helps :-)
