I made 8 pairs of corduroy trousers into one rag rug!
geeky note: This rug is a great way to see integration! You can see that the rug is made up of lots of circles, each circle is 6 stitches bigger than the previous. Therefore the change in circumference as a function of radius is 6.
If we differentiate the equation for the circumference of a circle (C=2πr), i.e. if we find out how C (the circumference) changes as we change r (radius) than we get dC/dr=2π which is approximately equal to 6.
So, we can work out the difference between the circumference and radius is 6 OR we can just count the stitches. I love it when you can weave a bit of maths into your crafts!