Determine the radius of the circle, if its length is 10, 833 m. Determine the diameter of the circle, if its length is 3, 297 dm.

The length of the circle and its diameter are connected by the constant p (read “pi”), which is equal to the ratio of the circumference of the circle to its diameter. The p value is usually rounded to the nearest hundredths and is considered equal to 3.14.

a) Given:

Circumference C = 10.833 m;

p = 3.14.

Find: R (radius).

Decision:

From the definition of p (that is, the formula p = C / d, where d is the diameter of the circle), we express d:

d = C / p.

The radius is equal to half the diameter, so we will find it by the formula:

r = C / 2p = 10.833 / 2 / 3.14 = 1.725 (m).

Answer: r = 1.725 m.

b) Given:

C = 3.297 dm;

p = 3.14.

Find: d.

Decision:

d = C / p = 3.297 / 3.14 = 1.05 (dm).

Answer: d = 1.05 dm.