Solving a chemistry problem

7(1). From V ml of aqueous 0.1 M solutions of salts, they are extracted in the form of hydroxyquinolates by threefold extraction with chloroform; a) lanthanum, b) samarium. The distribution coefficients are DLn=370, DSm=280. Calculate the minimum solvent consumption to extract each of the elements so that its concentration in the aqueous solution decreases to the final concentration c’.
OPTION 1
VLn, ml, VSm, ml s’, mol/l.
250 200 1*10-3