Find the circumference use 3 1/7 for pi
1. r= 28 ft.
2. D=98 cm
These two questions are making me nuts. I know they have got to be odvious.

age 7th grade.
Could you please show me how to work them?




The mathematical fact you need is that if you have a circle, no matter how large or small, the circumference divided by the diameter is always pi. Said another way

circumference = pi diameter

In your first example the radius is 28 feet. Since the diameter is twice the radius, the diameter is 56 feet. Thus the circumference is given by

circumference = (3 1/7) 56 = 176 feet

For the second problem the diameter is 98 feet so

circumference = (3 1/7) 98 feet



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