Answer: The circumference of the patio is 21.98 meters.
Step-by-step explanation: Given that there is a circular patio with a diameter of 7 meters. Greg is going to put a titled edge around the patio.
We are to find the circumference of the patio.
If 'r' units is the radius of a circle, then the circumference of the circle is given by

Since the diameter of the circular patio is 7 meters, so the radius 'r' will be given by

Therefore, the circumference of the patio is given by

Thus, the circumference of the patio is 21.98 meters.