The area of the base of a right circular cone is
7
1408
cm
2
and its height is 6cm. Taking π=
7
22
, the curved surface area of the cone is:
- A7
1670
cm
2 - B7
1068
cm
2 - C7
1760
cm
2 - D7
7160
cm
2
Solution & Step-by-step Explanation
The base of a cone is a circle. Therefore, Base Area=πr
2
.
7
22
×r
2
=
7
1408
22×r
2
=1408
r
2
=
22
1408
=64
r=8cm
Given height (h) = 6cm.
Slant height (l) is:
l=
r
2
+h
2
=
8
2
+6
2
=
64+36
=
100
=10cm
The curved surface area (CSA) of a cone is πrl:
CSA=
7
22
×8×10=
7
1760
cm
2
2
.
7
22
×r
2
=
7
1408
22×r
2
=1408
r
2
=
22
1408
=64
r=8cm
Given height (h) = 6cm.
Slant height (l) is:
l=
r
2
+h
2
=
8
2
+6
2
=
64+36
=
100
=10cm
The curved surface area (CSA) of a cone is πrl:
CSA=
7
22
×8×10=
7
1760
cm
2