Question

question
the diameter of a circle is 4 m. find its area to the nearest tenth.
answer attempt 1 out of 2
a = ​ m²
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Explanation:

Step1: Find the radius

The radius \( r \) of a circle is half of the diameter \( d \). Given \( d = 4\space m \), so \( r=\frac{d}{2}=\frac{4}{2}=2\space m \).

Step2: Calculate the area

The formula for the area \( A \) of a circle is \( A=\pi r^{2} \). Substitute \( r = 2\) into the formula: \( A=\pi\times(2)^{2}=\pi\times4\). Using \( \pi\approx3.14159 \), we get \( A\approx3.14159\times 4 = 12.56636\space m^{2}\).

Step3: Round to the nearest tenth

Rounding \( 12.56636 \) to the nearest tenth (one - decimal place). Look at the second - decimal digit (6). Since \( 6\geq5 \), we round up the first - decimal digit. So \( 12.56636\approx12.6\space m^{2}\).

Answer:

\(12.6\)