The wheels circumference is how many times as big as its diameter?

A wheel is in the shape of a circle.

The formula for the circumference of a circle is 2πr where r is the radius.

But, the diameter of a circle is twice the radius so this equation can be written, Circumference = πd where d is the diameter.

The Circumference is therefore π times as big as the diameter, π = 3.142 or 22/7 approx.