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.
(parent)
Could you please show me how to work them?

 
 

 

Hi,

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

Penny

 
 

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