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Basic Math Examples
r=3.5r=3.5
Step 1
The circumference of a circle is equal to Pi ππ times the diameter dd.
π⋅(diameter)π⋅(diameter)
Step 2
Since the diameter dd is equal to 22 times the radius rr, the formula for circumference using radius is 2πr2πr.
2π⋅(radius)2π⋅(radius)
Step 3
Substitute the value of the radius r=3.5r=3.5 into the formula for the area of a circle. Pi ππ is approximately equal to 3.143.14.
2⋅π⋅3.52⋅π⋅3.5
Step 4
Step 4.1
Multiply 3.53.5 by 22.
7π7π
Step 4.2
Multiply 77 by ππ.
21.9911485721.99114857
21.9911485721.99114857