The width of the sidewalk would be 10ft.
Sorry if incorrect
Answer:
169.56 cubic centimeters
Step-by-step explanation:
volume(cylinder) = 


(3.14)(3^2)(6)
(3.14)(9)(6)
169.56
Do you mean 8 more smaller if so the answer to your question is
X+y=40
Y=8 + x
Substituting the second equation into the first:
X+(8+x)=40
2x+8=40
2x=32
Smaller number: x=16
Y=8+(16)
Large number: y=24