Question 692963
The standard formula for finding the circumference of a circle is C = d * π or C = 2r * π, where d = the diameter, r = radius, and π = a value of approx. 3.14159 or 22/7 (depending on the context of the problem). The reason we could use either formula is because twice the radius of a circle equals its diameter, or 2r = d. So, we could use either or to solve for the circumference. Using our values, we have:


C = 2rπ
C = 2(7)(22/7)
C = 14(22/7) = approx. 44 in. (43.982 in).


C = dπ = 14(22/7) = approx. 44 in. (43.982 in).


OR


C = 14(3.14159) = approx. 44 in. (43.982 in).


NOTE: Depending on your course, it is extremely important to note the usage of pi in these answers. I have calculated the approximate value of pi and use that in my operations. Pi is not a constant number; it is irrational (never-ending decimal). If the problem wants the EXACT answer for this, then we need to simply leave the symbol for pi in our answer:


C = 14π in.