The RADII of the top and bottom of a frustum of a cone are 3cm and

Question

7.5cm respectively. If the height of the frustum is 30cm, calculate (i) the
curved surface area (ii) the volume of the frustum.
Note: show the workings

Answer 1

for the calculations.

(i) Curved Surface Area:

Let R = 3 cm, r = 7.5 cm, and h = 30 cm

Curved Surface Area = π(R + r) (√(R² + r² + h²))

= π(3 + 7.5) (√(3² + 7.5² + 30²))

= π(10.5) (√(90.25 + 225 + 900))

= π(10.5) (√1215.25)

= π(10.5) (34.9)

= 381.9π cm²

(ii) Volume of the Frustum:

Volume of the Frustum = (1/3)πh (R² + Rr + r²)

= (1/3)π(30) (3² + 3(7.5) + 7.5²)

= (1/3)π(30) (90 + 22.5 + 56.25)

= (1/3)π(30) (168.75)

= 1575π cm³

Answer 2

I hate how bots post a dozen similar problems all at once.
and then other bots answer them, usually wrong.

Answer 3

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Answer 4

(a) Draw an addition⊕ and multiplication ⊗ tables for arithmetic modulo 6.
(b) Use your tables to solve these equations:
(i) 5⊗n=1 (ii) 2⊕n=0 (iii) 2⊕(3 ⊕n)=1