A grinding ratio of 200 implies that the

1. grinding wheel wears 200 times the volume of the material removed.
2. grinding wheel wears 0.005 times the volume of the material removed
3. aspect ratio of abrasive particles used in the grinding wheel is 200
4. ratio of volume of abrasive particle to that of grinding wheel is 200

Grinding ratio is defined as

=	Volume of work material removed (V_m)
	Volume of wheel wear (V_w)

200 =	Volume of work material removed (V_m)
	Volume of wheel wear (V_w)

Grinding wheel wears 0.005 times the volume of material removed.