8. From a solid cylinder whose height is 2.4 cm and diameter 1.4 cm, a conical cavity of the
same height and same diameter is hollowed out. Find the total surface area of the
remaining solid to the nearest cm.
Is this not the solution?
Answers
Answer:
Given:
Height (h) of the conical part = Height (h) of the cylindrical part =2.4 cm
Diameter of the cylindrical part =1.4 cm
Radius =
2
Diameter
Radius(r) of the cylindrical part =0.7 cm
Slant height (l) of conical part =
r
2
+h
2
=
0.7
2
+2.4
2
=
0.49+5.76
=
6.25
=2.5
Total surface area of the remaining solid = CSA of cylindrical part + CSA of conical part + Area of cylindrical base
=2πrh+πrl+πr
2
=2×
7
22
×0.7×2.4+
7
22
×0.7×2.5+
7
22
×0.7×0.7
=4.4×2.4+2.2×2.+2.2×0.7
=10.56+5.50+1.54=17.60 cm
2
The total surface area of the remaining solid to the nearest cm
2
is 18 cm
2
Step-by-step explanation:
I hope it help you
