The avoid ratios at the densest, loosest and the natural

The avoid ratios at the densest, loosest and the natural states of a sand deposit are 0.2, 0.6 and 0.4, respectively, the relative density of the deposit is

I_D =	e_max - e	× 100
	e_max - e_min

=	0.6 - 0.4	× 100
	0.6 - 0.2

=	0.2	× 100 = 50%
	0.4