haha well I had a quick shot at it, and my answer feels wrong so I will post it and have someone explain....
I have the circumference of the earth in metres as 40,000,000
so the diameter of this earth is 12732395
I am adding 1 metre stick to each radius, and 2 to the diamter and times by pi to get the new circumference;
giving 6 extra metres, which seems crazy...