# What is the circumference of a circle if the diameter is 1.6?

Sep 9, 2015

Circumference $= 5.0$

#### Explanation:

Formula for circumference of circle is $\pi d$
$\textcolor{w h i t e}{\text{XXXX}}$where $d$ is the diameter, and
$\textcolor{w h i t e}{\text{XXXX}} \pi$ (approximately $3.14159$) is a standard constant.

With a diameter of $1.6$
$\textcolor{w h i t e}{\text{XXXX}}$circumference $= \pi \cdot 1.6$

$\textcolor{w h i t e}{\text{XXXXXXXXXXXX}} \approx 3.14159 \cdot 1.6$

$\textcolor{w h i t e}{\text{XXXXXXXXXXXX}} \approx 5.02654$

Since the diameter is only given to 2 places of accuracy, the computed average should be rounded to 2 places as well:
$\textcolor{w h i t e}{\text{XXXX}}$circumference $= 5.0$