Tim has to cover 3 tanks completely with paint. Each tank is in the shape of a cylinder with a top and a bottom.

The tank has a diameter of 1.4 metres and a height of 1.9 m.

A tin of paint covers 5 m

Find the total surface area of the 3 tanks and state how

many tins of paint Tim will need to buy.

You must show your working.

a)

the total surface area of the 3 cylinders is11.4296 m²

b)the number of tins paints that Tim will need to buy is 7 tins of paints.

Step-by-step explanation:

Given:

Height = 1.9m

Diameter = 1.4m

The radius = diameter/2 = 1.4/2 = 0.7

From the question, each of the tank is cylindrical in shape we can make use of surface area of the cylinder formula in calculating this.

Total surface area = (2πr² + 2πrh)

Where

r = the height of the cylinder.

h = the height of the cylinder.

π = 3.14 or 22/7

Total surface area = (2 × 3.14 × 0.7²) + (2 × 3.14 × 0.7 × 1.9 )

= (3.0772 + 8.3524)

= 11.4296 m²

Then to calculate the total surface area of the 3 cylinders we multiply by 3.

= 11.4296 × 3

= 34.29 m²

But the question says a tin of paint covers 5 m², then the number of tins paints that Tim will need to buy can be calculated as

=34.29/5

= 6.858

If we round it up to whole number we have 7 tins of paints.

Therefore, the number of tins paints that Tim will need to buy is 7 tins of paints.