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# A solid iron pole consists of a cylindrical height 220 cm and base diameter 24 cm, which is surmounted by another cylinder of height 60 cm and radius 8 cm. Find the mass of the pole, given that 1 cm3 of iron has approximately 8 g mass. (Use $$\pi \ = \ 3.14$$ )

Volume of the solid iron pole = Volume of the cylindrical portion + Volume of the other cylindrical portion

$$= \ \pi (r_1)^2 h_1 \ + \ \pi (r_2)^2 h_2$$

$$= \ 3.14 \ × \ (12)^2 \ × \ 220 \ + \ 3.14 \ × \ (8)^2 \ × \ 60$$

$$= \ 3.14 \ × \ 144 \ × \ 220 \ + \ 3.14 \ × \ 64 \ × \ 60$$

$$= \ 99475.2 \ + \ 12057.6$$

$$= \ 111532.8$$ cm3

$$\therefore$$ The mass of the pole
$$= \ 111532.8 \ × \ 8$$ grams

$$= \ \frac{111532.8 \ × \ 8}{1000} \ = \ 892.26$$ kg