# How do you find the circumference of a circle with a diameter of 4.4 cm?

Use the formula $c = \pi d$ to obtain circumference $\cong 13.823$
The constant $\pi$ is the ratio of the circumference of a circle to its diameter (i.e. $\pi = \frac{c}{d}$) or more commonly $c = \pi \cdot d$ (where $c$ is the circumference and $d$ is the diameter).
You can use a calculator to evaluate this (if your calculator does not have the constant $\pi$ assigned to a button, you can use $3.14159$ which is a reasonable approximation for virtually all situations)