Question

the diameter of a circle is 13 in. find its area to the nearest whole number.

Explanation:

Step1: Find the radius

The radius $r$ of a circle is half of the diameter $d$. Given $d = 13$ in, so $r=\frac{d}{2}=\frac{13}{2}=6.5$ in.

Step2: Calculate the area

The formula for the area $A$ of a circle is $A=\pi r^{2}$. Substitute $r = 6.5$ in, we get $A=\pi\times(6.5)^{2}=\pi\times42.25$. Using $\pi\approx3.14$, then $A\approx3.14\times42.25 = 132.665$ square - inches.

Step3: Round to the nearest whole number

Rounding $132.665$ to the nearest whole number gives $133$ square - inches.

Answer:

$133$ square - inches