To find the approximate circumference of a circle, you can use the formula:
\[ \text{Circumference} = \pi \times \text{diameter} \]
Given a diameter of 20 and using \( \pi \approx 3.14 \):
\[ \text{Circumference} = 3.14 \times 20 = 62.8 \]
Thus, the approximate circumference of the circle is 62.8.