Dry weight of an organ for a pool of n plants - Computation

Calculate the dry weight of the organs of a pool of n plants, based on the fresh weight of the organs of n plants and the dry matter content of the organ. Here the dry matter content of the tillers is calculated as the average dry matter of the different organs of the main shoot (the hypothesis is that the tillers have the same proportions of the different organs than the main shoot, what is wrong). The number of plants (n) must be provided. Recommended range for n is 3 to 6.