
288 Chapter 7
so far the square is winning
So, when it comes to providing butt-space for a 3 cubic
meter volume of water, the square shaped hot tub is better
than the circle shaped one.
The square tub beats the circle tub
Both tubs are the same depth.
Both tubs have the same area.
Work the formula for circle area backward to get the butt count
for the circle shaped hot tub.
circle area = ∏r
2
perimeter = 2
∏r
Butts = perimeter
6 =
∏r
2
∏ 3.1415
6 = 6
0.5
0.5 = 17.3 butts
P = 2 x 3.1415 x 1.38
P = 8.67m
Butts = 8.67
= r
2
1.9m
2
= r
2
1.38m = r
radius
17.3 butts
19.6 butts
6m
2
Circumference in the
case of a circle
That’s m for meters, not a new variable!
Or 17.4 butts if you didn’t round
as you worked—either is OK.