Answer:
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.
