Answer:
8
Step-by-step explanation:
The area of a circle with twice the radius is 4 times the area of the smaller circle. If John's hours are proportional to area, we expect it will take him 4 times as long for the larger area.
John can expect to take 8 hours cutting the grass in the larger lawn.
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The area of a circle with radius r is ...
A = πr²
The area of a circle with radius 2r is ...
π(2r)² = 4πr² = 4A . . . . . 4 times the area of the smaller circle
