Answer: 94.2 cm
Step-by-step explanation: To find the circumference of the circle shown here, start with the formula c = 2πr.
Notice that here, we're given the diameter instead of the radius. Remember that the radius is equal to half of the diameter. So here, the radius will be equal to half of 30 cm or 15 cm.
So we can plug in 15 cm for <em>r</em> in the formula.
So we have (2) (π) (15 cm) which is equal to 30π cm.
Remember that π is approximately equal to 22/7 or 3.14 so we can estimate the value of the circumference by plugging in 3.14 for π.
So we have (30) (3.14) which is equal to 94.2.
So the circumference of the circle is approximately equal to 94.2 cm.
It's important to understand that we could have also used
the formula c = πd since 2 times the radius is equal to the diameter.
