Answer:
[tex]Area = 162\ m^2[/tex]
Step-by-step explanation:
Given
[tex]Scale = 1:45[/tex]
[tex]Scale\ Drawing = 20cm\ by\ 40cm[/tex]
Required
Determine the actual area
First, we need to determine the actual measurements:
[tex]Length = 45 * 20cm[/tex]
[tex]Length = 900\ cm[/tex]
Convert to metres
[tex]Length = 900 * 0.01\ m[/tex]
[tex]Length = 9\ m[/tex]
[tex]Width = 45 * 40cm[/tex]
[tex]Width = 1800\ cm[/tex]
Convert to metres
[tex]Width = 1800 * 0.01\ m[/tex]
[tex]Width = 18\ m[/tex]
The area can then be calculated as
[tex]Area = Length * Width[/tex]
[tex]Area = 9\ m * 18\ m[/tex]
[tex]Area = 162\ m^2[/tex]