1) Circumference of Earth: Diameter x π → 12,800 x π = 40,212.39 km

2) time in Hour = distance/speed → distance = 40,212.39 and speed = 2 Mi/h

1st: convert miles into km : 1 mile = 1.609344 km and 2 miles = 3.218688 km
2nd: convert speed into km/h → speed = 3.218688 km/h
And time in hour = 40,212.39 / 3.218688 → time = 12,493 hours OR in days:
12,493 / 24 = 521 days (OR 104 weeks, including 2 days of rest)

4 0

3 years ago

Find the circumference of a circle that has an area of 452.16 square meters. (Use 3.1416 as the value of π.)

laila [671]

$\bf \textit{area of a circle}\\\\
A=\pi r^2\quad 
\begin{cases}
r=radius\\
-----\\
A=452.16
\end{cases}\implies 452.16=\pi r^2\implies \cfrac{452.16}{\pi }=r^2
\\\\\\
\boxed{\sqrt{\cfrac{452.16}{\pi }}=r}\\\\
-------------------------------\\\\
\textit{circumference of a circle}\\\\
C=2\pi r\qquad \qquad \implies C=2\pi \left( \boxed{\sqrt{\cfrac{452.16}{\pi }}} \right)$

so, is just that product, recall to use "<span>3.1416 as the value of π".</span>

7 0

3 years ago