Question

the diameter of a circle is 15 cm. 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 $d = 15$ cm, so $r=\frac{d}{2}=\frac{15}{2}=7.5$ cm.

Step2: Calculate the area

The formula for the area $A$ of a circle is $A=\pi r^{2}$. Substitute $r = 7.5$ cm into the formula: $A=\pi\times(7.5)^{2}=\pi\times56.25$. Using $\pi\approx3.14$, we have $A\approx3.14\times56.25 = 176.625$ $cm^{2}$.

Step3: Round to the nearest whole number

Rounding $176.625$ to the nearest whole number gives $177$ $cm^{2}$.

Answer:

$177$ $cm^{2}$