Answer:
£94
Step-by-step explanation:
Basically, we want to find the surface area of this cylinder.
The surface area of a cylinder is denoted by: A = 2πr² + 2πrh, where r is the radius and h is the height. However, note that the farmer only wants to paint the curved surface of the cylinder, so we don't want to include the 2πr² part that accounts for the two circular bases. Instead, we actually just want to find the value of 2πrh.
Here, we see that the diameter is 8 metres, so since the radius is half the diameter, we know that r = 8/2 = 4 metres.
We also see that the height is 6 metres, so h = 6.
Plug these numbers in:
2πrh
2π * 4 * 6 = 48π ≈ 150.8 m²
We see that each can of paint will cover 20 m², so divide 150.8 by 20 to find the number of cans we need:
150.8 ÷ 20 = 7.5 ≈ 8 cans
Each can costs £11.75, so multiply 8 by 11.75 to get the total cost:
11.75 * 8 = £94
The answer is £94.
