There's a simple formula for the area of an ellipse: pi*a*b, where a and b are , half the lengths of the long axis and the short axis respectively.
Here, A = pi*(12 ft)(4 ft) = 48 pi ft^2, or about 150.8 ft^2.
(2/3) / 3 = 1/x...2/3 to 3 lawns = 1 to x lawns
cross multiply
(2/3)(x) = (3)(1)
2/3x = 3
x = 3 * 3/2
x = 9/2 or 4 1/2 lawns can be cut with a full tank of gas
The answer is 3 ft
The surface area (SA) of a cylinder with radius r and height h is:
SA = 2πr² + 2πrh = π(2r² + 2rh)
We have:
SA = 126π ft²
h = 3 * d
d = 2r
h = 3 * 2r = 6r
126π = π(2r² + 2rh)
126 = 2r² + 2rh
126 = 2r² + 2r * 6r
126 = 2r² + 12r²
126 = 14r²
r² = 126/14
r² = 9
r = √9
r = 3
