Let's the weight of Case C = "x" grams.
From the information:
Case A = 12 times heavier than Case B,
Therefore, the weight of Case B = 1/12 of Case A's weight:
Weight of Case B = (1/12) * Weight of Case A
Case B = 16 times heavier than Case C,
so, weight of Case C = 1/16 of Case B's weight:
Weight of Case C = (1/16) * Weight of Case B
The weight of Case A = 8,640g,
Let's substitute the value into the equations to find the weight of Case C:
Weight of Case B = (1/12) * 8,640 = 720g
Weight of Case C = (1/16) * 720 = 45g
Thus, the weight of Case C is 45 grams.