Question

what is the area of a circle with a diameter of 18 mm? use 3.14 for pl. enter your numeric answer with no label to the hundredths place position.

Explanation:

Step1: Find the radius

The radius \(r\) of a circle is half of the diameter \(d\). Given \(d = 18\) mm, so \(r=\frac{d}{2}=\frac{18}{2}=9\) mm.

Step2: Use the area formula

The area formula of a circle is \(A=\pi r^{2}\). Substitute \(\pi = 3.14\) and \(r = 9\) into the formula: \(A=3.14\times9^{2}\).
First, calculate \(9^{2}=81\). Then \(A = 3.14\times81\).
\(3.14\times81=(3 + 0.14)\times81=3\times81+0.14\times81=243+11.34 = 254.34\)

Answer:

254.34