After dehydrating 8 kg of potatoes with 98% water content, the new weight is 3.2 kg, assuming the water content after dehydration is 95%.
The 8 kg and 98% water content potatoes have 0.16 kg dry mass and 7.84 kg water mass. Since dehydration only impacts the water mass, the dry weight would remain the same after dehydration, i.e., 0.16 kg. And the water content at 95% hydration becomes 3.04 kg. Read more