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KrayzKajun
01-22-2010, 07:06 AM
im havin a brain fart right now!!

tryin to figure out the square footage for a circle driveway addition.

16ft wide

top of curve is 88ft long, bottom of curve is 65ft long.

im stumped on doin the square fooyage of an irregular shape!

xtreem3d
01-22-2010, 11:03 AM
202 sq ft if it was a true circle

http://www.gardenplace.com/content/calculator/area_calc.html#

irregular shape http://mathforum.org/library/drmath/sets/select/dm_area_irreg.html

AWJ Services
01-22-2010, 11:30 AM
If the whole drive is 16 ft wide you can just measure the center and multiply by the width and that will get you a pretty accurate number.

Another way is if the area is a circle just take the 2 areas and subtract from each other.

Circumfrence is 88 ft. C=pie x diameter.
0r D=C/pie
D=28ft
for the second circle D=20 ft
That leaves only an 4 ft wide drive so you must not be dealing with a circle.
I will finish the calculation.

Areacircle is pie x radius squared.Radius is 1/2 D

Area first circle is 615
Aea second circle is 314

1st minus 2nd equals 301 sq/ft




Another way is to just straighten the circle.
That means one side of the drive will be 88 and the other side will be 65.

Then connect the short end to the long end which will leave a right triangle at the end to solve.

That would be 65 ft x 16 ft = 1040
Then the triangle will be 88- 65 = 23

23 x 16 divided by 2 which = 184

then add the 2 numbers 1040 +184= 1224.

Since these 2 numbers do not equal then you either measured wrong or it is not a complete circle.

The second way of figuring will work for and drive regardless of shape.
The first will only work for a true circle.

KrayzKajun
01-23-2010, 01:48 PM
its more of a half moon shape!

1idejim
01-26-2010, 08:23 PM
If the whole drive is 16 ft wide you can just measure the center and multiply by the width and that will get you a pretty accurate number.

Another way is if the area is a circle just take the 2 areas and subtract from each other.

Circumfrence is 88 ft. C=pie x diameter.
0r D=C/pie
D=28ft
for the second circle D=20 ft
That leaves only an 4 ft wide drive so you must not be dealing with a circle.
I will finish the calculation.

Areacircle is pie x radius squared.Radius is 1/2 D

Area first circle is 615
Aea second circle is 314

1st minus 2nd equals 301 sq/ft




Another way is to just straighten the circle.
That means one side of the drive will be 88 and the other side will be 65.

Then connect the short end to the long end which will leave a right triangle at the end to solve.

That would be 65 ft x 16 ft = 1040
Then the triangle will be 88- 65 = 23

23 x 16 divided by 2 which = 184

then add the 2 numbers 1040 +184= 1224.

Since these 2 numbers do not equal then you either measured wrong or it is not a complete circle.

The second way of figuring will work for and drive regardless of shape.
The first will only work for a true circle.

if you are truly 16 ft. throughout the lenght then you can split the difference between long and short 65-88 = 76.5 x16 = 1224

AWJ Services
01-26-2010, 08:42 PM
if you are truly 16 ft. throughout the lenght then you can split the difference between long and short 65-88 = 76.5 x16 = 1224

Thats correct. Thats why I said it's best just to measure the center of the arc which is what your calculation has given him.

KrayzKajun
01-27-2010, 12:14 AM
Thanks fellas