SmarterEd

Aussie Maths & Science Teachers: Save your time with SmarterEd

Unit Conversion, SM-Bank 010

A circle is drawn from a city centre with a radius of 800 metres.

Using the conversion ratio, 1 km² = 1 000 000 m², determine the area of the circle in square kilometres, to two decimal places.  (2 marks)

Show Answers Only

\( 2.01 \text{km}^{2}\)

Show Worked Solution
\(\text{Area}\) \(= \pi \times 800^{2}\ \text{m}^{2} \)  
  \(= 2\ 010\ 619\ \text{m}^{2}\)  
  \(= \dfrac{2\ 010\ 619}{1\ 000\ 000} \)  
  \(=2.01\ \text{km}^{2} \)