The distance across a sink drain is 3.8 cm. Identify the measurement as either the diameter, radius, or circumference. The estimate the other two measurements.

Question

What I mean by estimate the other two measurements is for example if another problem has a minute hand on the clock and it is 5 inches and the 5 inches represents the radius I would have to find out what is the diameter and circumference which are the other 2 measurements.

Answer 1

If you picture a sink drain, the shape is usually a circle. Therefore, if you are taking the measurement all the way across it, the distance is the diameter. The diameter is given as 3.8cm.

The radius would be half of the distance across the drain, or half of the diameter. Half of 3.8cm, or 3.8cm / 2 is 1.9cm.

The circumference is the distance around the drain, or if you trace the entire circle. The formula to find the circumference of a circle is 2 multiplied by pi and the radius of the circle, or C = 2(pi)r. Here, we just found the radius, so the circumference is 2 * pi (which is approximately 3.14) * 1.9cm, or approximately 11.9cm!