3. The diameter of a cylindrical column is 60cm and its height is 4.2m
The cost of making it is £67.50 per cubic metre.
What is the cost of making it?

£80.33

Step-by-step explanation:

The formula for the Volume of a cylinder = πr²h

The diameter of a cylindrical column is 60cm and its height is 4.2m

Converting the diameter to meter

100 cm = 1 m

60 cm = x

Cross Multiply

100 × x = 60 × 1

x = 60/100

x = 0.6m

The diameter of the cylinder = 0.6m

Radius = Diameter/2

Radius = 0.6m/2

Radius = 0.3m

Volume of a cylinder = πr²h

= π × 0.3² × 4.2

= 1.18752 m²

Approximately = 1.19 m²

The cost of making it is £67.50 per cubic metre. What is the cost of making it?

The volume of the cylindrical column = 1.19 m²

Hence:

1m² = £67.50

1.19m² = x

Cross Multiply

x × 1m² = 1.19 m² × £67.50

x = 1.19 m² × £67.50/1 m²

x = £ 80.325

Approximately = £80.33

Therefore, the cost of making the cylindrical column = £80.33

d.192

step-by-step explanation:

12*16=192