SOLUTION: A circular pool measures 16 feet across. One cubic yard of concrete is to be used to create a circular border with uniform width around the pool. The border is to have a depth of 4
Question 1063495: A circular pool measures 16 feet across. One cubic yard of concrete is to be used to create a circular border with uniform width around the pool. The border is to have a depth of 4 inches, how wide will the border be? (1 cubic yard=27 cubic feet) Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A circular pool measures 16 feet across. One cubic yard of concrete is to be used to create a circular border with uniform width around the pool.
The border is to have a depth of 4 inches, how wide will the border be?
(1 cubic yard=27 cubic feet)
:
let w = the width of the border
:
Find the area of the pool (r = 8)
A =
A = 201.062 sq/ft
Find the overall area. r = (w+8)
A =
A =
Overall area - pool area = border area
The volume of the border area = 27 cu/ft
4" = 1/3 ft = 27
multiply both sides by 3
divide both sides by pi
using the quadratic formula, I got a positive of
w = 1.475 ft is the width of the border
:
:
we can check this (pool volume is 4" thick also)
overall vol - pool volume = 27 cu/ft - =
94.0128 - 67.021 = 26.99 ~ 27 cu/ft which is 1 cubic yd