It is because your 1 inch is one circle 1 inch one circle one of each get it.
A 6 inch circle is the measurement from one edge through the centre to the opposite edge. This line is known as the circle's diameter.
A circle with a 12 inch diameter has a 6 inch radius.
The circumference of a six-inch diameter circle is: 18.8 inches.
The circumference of 9 inch diameter circle is about 28.27 inches.
The circumference of a circle with a 20.5 inch diameter is 64.4 inches.
The circumference of a circle with a 39 inch diameter is 122.52 inches.
The Diameter of a Circle is twice the Radius.thus for a 52 inch Diameter Circle the Radius will be 52/2=26 inches.
one inch is one inch; one inch dia refers to one inch diameter of a circle; it is still one inch
The circumference of a 10-inch diameter circle is: 31.4 inches.
A US 25 cent piece, a quarter, is close to one inch in diameter; it is just short. Its diameter is just about 15/16 of an inch. The diameter of a circle is the length all the way across the face of the circle going straight through the center. So a quarter gives you a good estimate of a circle with one inch diameter. Just imagine a circle very slightly bigger across.If you take an ordinary lead pencil and trace a circle using a US quarter as your template, you'll probably come even closer to a one inch diameter circle. Test it out with a ruler handy so you can get a better sense of it.
The area of 3.5-inch diameter circle is: 9.621 square inches.