Problema Solution

suppose that 20 turns of a wire are wrapped around a pipe with a length of 10 inches and a circumference of 12.5 inches. What is the length of the wire?

Answer provided by our tutors

After you roll the pipe out flat you get the following picture:    

Note that there are 20 pieces of ribbon each of which has length equal to the hypotenuse of a right triangle with sides 0.5 in and 12.5 in.

Using the Pythagorean Theorem we find the length of each piece:

Since there are 20 pieces the total length of the wire is 20 times the above length or:

 

The length of the wire is 250.2 inches.