English system is indeed based on the metric system because they look for reference stuff to get the measurements, for instance, a foot equals 30.48 cm, but a common 30-cm rule measures every 1 cm, so the metric system also provides more accurate measurements. An other example lies on the measurement of mass, a pound which equals 453.59 g is appropriated to measure middle amounts of masses, but for example, in qualitative analysis we tend to measure amounts below about 0.10 g (0.022 lb) so it is easier for us in science to use the metric system in addition to the straightforwardness of the reporting data in 10-based notation (scientific notation).
