SOLUTION: A circular fish pond with a diameter of 4 m, has circular paving that is 1,2 m wide around it. The litres of paving paint that will have to be bought to cover the paving if 2 litr

Algebra ->  Customizable Word Problem Solvers  -> Geometry -> SOLUTION: A circular fish pond with a diameter of 4 m, has circular paving that is 1,2 m wide around it. The litres of paving paint that will have to be bought to cover the paving if 2 litr      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 1047149: A circular fish pond with a diameter of 4 m, has circular paving that is 1,2 m wide around it. The litres
of paving paint that will have to be bought to cover the paving if 2 litres are needed per square metre,
rounded to the nearest litre, is . . . .
[1] 39 ℓ
[2] 40 ℓ
[3] 20 ℓ
[4] 69 ℓ

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The whole pond and paving has diameter 6.4 meters , 4 for the pond and 1.2 m on each side.
The area of the whole circle with radius 3.2 meters, half of 6.4, is pi*(3.2^2)=32.17 m^2.
The area of the pond with radius 2 meters, half of 4, is 4pi=12.57 m^2.C
Therefore, the area of pavement is the difference, or 19.60 m^2
If there is 2 liters of pavement/m^2, then the paint needed would be 39.2 or 39 liters to the nearest l.
Choice [1].