Question

Question 4
a) A toy is in the form of a cone mounted on a cylinder with the same radius. The slant height
and the diameter of the base of the conical portion is 10 cm and 12 cm respectively. The total
height of toy is 21 cm. Determine the volume of the toy.
Cindth
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of their​

Answer 1

Answer:

Conical portion

r=3cm,h=4cm

l

2

=r

2

+h

2

=3

2

+4

2

=9+16

l

2

=25

l=

25

=5cm

Spherical portion r=3cm

Surface area of the toy= CSA of hemisphere+ CSA of cone

=2πr

2

+πrl=2×

7

22

×3×3cm

2

+

7

22

×3×5cm

2

=

7

396

cm

2

+

7

330

cm

2

=

7

726

cm

2

=103.71cm

2

Surface area of the toy=103.71cm

2

Volume of the toy= Volume of hemisphere+ Volume of cone

=

3

2

πr

3

+

3

1

πr

2

h=

3

2

×

7

22

×3×3×3cm

3

+

3

1

×

7

22

×3×3×4cm

3

=

7

396

cm

3

+

7

264

cm

3

=

7

660

cm

3

∴ Volume of the toy=94.28cm

3

.

solution