A raw material (ore) contains 4.50 wt. % Pb and 6.90 wt. % Zn. After ore-dressing by flotation, 40 metric tons of bulk concentrate having 18.21 wt. % Pb and 40.20 wt. % Zn is obtained from 250 metric...

Extracted text: A raw material (ore) contains 4.50 wt. % Pb and 6.90 wt. % Zn. After ore-dressing by flotation, 40 metric tons of bulk concentrate having 18.21 wt. % Pb and 40.20 wt. % Zn is obtained from 250 metric tons of ore per day. Calculate (a) recoveries of lead and zinc to concentrate (%). and (b) the total weight and Pb and Zn percentages (%) of the discarded gangue (tailing)