Extension to Other Molecular Weight Averages

We may define an average in general as the ratio of successive moments of the distribution. We have seen above that Mn, the number average molecular weight, is equal to the ratio of the first to the zeroth moment of the number distribution. If we now take ratios of successively higher moments of the number distribution, other average molecular weights are described ,  

Problem 4.3 A sample of poly(vinyl chloride) is composed according to the following fractional distribution  

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