A woman has invited her family for dinner. She has prepared a large pot of soup as an appetizer. She puts it in her yard in the morning to cool down and forgets to cover it. There are 100 kg of soup in the pot, 98 % of which is water. Unfortunately, it starts to rain heavily and the pot is still not covered. At noon, the soup has a water content of 99 %.
How much does the soup weigh now?
The soup now weighs 200 kg. In the morning it weighs 100 kg, of which 98 % (i.e. 98 kg) is water. 2 kg (100 kg - 98 kg = 2 kg) of the soup are greens. After the rain, the 2 kg of greens make up only 1 % of the total weight (99 % is now water). So 1 % corresponds to 2 kg, and 100 % then corresponds to 200 kg.