Relation between number of average molecular mass `(overline(M)_(n))` and weight of average molecular mass `(overline(M)_(w))` of synthesized polymers is

What is the average molecular mass of drugs ?

Number-average molecular mass of a polymer is determined by:

The number average molecular mass and mass average molecular mass of a polymer are respectively 30,000 and 40,000. The poly dispersity of the polymer is:

Mass-average molecular mass of a polymer is determined by:

The PDI (polydispersity index) is the ratio of weight to number-average molecular masses (Mbar(w))//(M(bar(n)) .In natural polymers,which are generally monodispersed, PDI is………and in synthetic polymers which are always polydispersed, PDI is …….. because Mbar(w) is always .......than Mbar(n) .

In a polymer sample, 30% of molecules have a molecualr mass of 20,000, 40% have 30,000 and the rest 60,000. What is the weight average molecular mass of the polymer?