Ok so, it all depends if Shane is likely to jump win over all of the other seventh graders then the eighth graders should earn the 50 points...
But if the roles are reversed the the Seventh graders should earn the 50 points.
There is not a full answer to what I am saying but from speculation you should be able to decide..
Answer:
perimeter: 26
area: 16 + 10 =26
perimeter: add all lengths.
area: multiply LxW
The slope would be positive in this case
If you visualize the problem, there are two concentric circles, the pool, and the pool plus the walkway. So, we have to subtract the area of these two concentric circles to find the walkway.
Bigger circle: Pool plus walkway
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diameter = 18 + 4(2) -- this is because there is 2 ft of walkway at each far end
diameter = 26 ft
Area = pi*(26/2)^2
Area = 530.93 ft2
Smaller circle:pool
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diameter = 18 ft
Area = pi*(8/2)^2
Area = 50.27 ft2
Area of walkway
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A = 530.93 - 50.27
A = 480.66 ft2
Then the cost would be
Cost = $4.25 * 480.66
Cost = $2,042.81