From a solid cylinder whose height is 24 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?
plz do fast
Answers
Step-by-step explanation:
MATHS
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
2
. (Use π=
7
22
).
Help best friend
Study later
VIDEO EXPLANATION
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