The plan of a survey plotted to a scale of 10 m to 1 cm

The plan of a survey plotted to a scale of 10 m to 1 cm is reduced in such a way that a line originally 10 cm long now measures 9 cm. The area of the reduced plan is measured as 81 cm². The actual (m²) of the survey is

Actual area =		Actual scale		²	× measured area × scale
		Reduced scale

=	100	× 81 × 100 = 10000 m²
	81