Question

use the information given to answer the question. consider the circle with a diameter of 42 millimeters. part a what is the approximate area of the circle, rounded to the nearest hundredth of a square millimeter? (use 3.14 as an approximation of pi.)

Explanation:

Step1: Find the radius

The radius $r$ of a circle is half of the diameter $d$. Given $d = 42$ mm, so $r=\frac{d}{2}=\frac{42}{2}=21$ mm.

Step2: Calculate the area

The area formula of a circle is $A=\pi r^{2}$. Substitute $r = 21$ mm and $\pi\approx3.14$ into the formula: $A\approx3.14\times21^{2}=3.14\times441 = 1384.74$ $mm^{2}$.

Answer:

$1384.74$ $mm^{2}$