How long is the rattan?
I have seen this problem, too.
In fact, you spread out the whole rattan.
The rattan walked seven times along the circumference of 3*7=2 1 foot.
I walked 20 feet along the height again.
pythagorean theorem
Root number Root number (20*20+2 1*2 1)= root number 84 1 = about 45.5 feet.