Question

how many cubic decimeter of concrete materials will be necessary to construct two cylindrical pillars each of whose diameter is 5.6 decimeter and height is 2.5 meter​

Answer 1

Step-by-step explanation:

Diameter of a cylindrical pillar = 5.6dcm.

Radius of a cylindrical pillar = 5.6 / 2 dcm.

= 28/10 dcm.

Height of a cylindrical pillar = 2.5 m.

= 2.5*10 dcm.

= 25 dcm.

Required material to construct 2 pillars= 2 * volume of cylindrical pillar

$= 2 \times \pi {r}^{2} h \: \: \: cubic \: unit$

$= 2 \times \frac{22}{7} \times \frac{28}{10} \times \frac{28}{10} \times 25 \: \: cu \: \: dcm$

$= 11 \times 28 \times 4 \: \: cu \: \: dcm$

$= 1232 \: \: \: cu \: \: dcm.$

Answer :- 1232 cubic decimetre of concrete materials will be used to construct 2 cylindrical pillars.