Fresh grapes contain 80% water, while dry grapes contain 10% water. If the weight of dry grapes is 500 kg, then what is its total weight when it is fresh?

Let the weight of fresh grapes be W.
Quantity of water in it = (80/100) x W = 4W/5
Quantity of pulp in it = W - (4W/5) = W/5
Quantity of water in 500 gm dry grapes
= (10/100) x 500 = 50 kg
∴ Quantity of pulp in it = (500 -50) = 450 kg
W/5 = 450
∴ W = 2250 kg