What is the diameter of the circle circumference is 30 X inches

188.5 in.

Step-by-step explanation:

The circumference of a circle is given by:

2πr Where r is the radius, and π is the ratio of the circumference of a circle to its diameter.

We have radius = 30

∴

2 (30) π = 60 π

If π ≈ 3.1416

2 (30) (3.1416) = 188.5in.