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find the circumferance of a circle that has a diameter of three inches. Give exact value

find the circumference of a circle that has a diameter of three inches. give exact value

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Arthur D. | Effective Mathematics TutorEffective Mathematics Tutor
5.0 5.0 (9 lesson ratings) (9)
  =9.42477 in
this is not an exact value because pi is an irrational number, a non-ending, non-repeating decimal,
in other words, it cannot be written as a simple fraction a/b
Jason S. | My goal is the success of my students. Knowledge-Patience-HonestyMy goal is the success of my students. K...
4.9 4.9 (115 lesson ratings) (115)
Circumference = pi(D) = (pi)(3) = 3pi or 3π. That's the EXACT value.

Approximate value would be using 3.14 for pi
x 3
9.42 in.


Michael F. | Mathematics TutorMathematics Tutor
4.7 4.7 (7 lesson ratings) (7)
What is wrong with 3π as an exact answer?  I admit it is not possible to write it as a decimal, but that was not the question.


C=3pi as an answer seems too easy for a homework problem. Secondly, the word exact may have different meanings for different people. Maybe to the student exact meant 3 times some approximate value of pi. Or maybe 3pi is what the student was looking for. Anyway, we gave him both answers to choose from.