a rope 60m long and 5cm in diameter is coiled tightly. Estimate, correct to one significant figure, the radius of the 'circle' formed. ( please could we have working out).

2 answers

The lateral surface area of the rope is 60m*5cm = 6000cm*5cm = 30,000 cm².
A circle with the same area and radius r is
πr² = 30000
Solve for r to get
r=sqrt(30000/π)=98 cm, or 0.98 m.
or 1 m to one significant figure.
I don't know answer