Today's puzzle will require some mental gymnastics to figure out the solution. Enjoy!
A truck is loaded up at the farm with ten tonnes of blueberries destined for a processing factory (we don't much care what will happen to them - maybe packaged for sale as fresh fruit, perhaps canned, who knows). Before the truck leaves, the berries are tested and found to be 99% water.
Some hours later, upon arrival at the processing plant, the load is again tested and found to now be 98% water.
Upon hearing about this seemingly minor discrepancy, the farmer is absolutely furious. Why?
As usual, answers in the comments below. Enjoy!