After four days of crossing a cargo ship sank and only part of the crew could be saved in the lifeboat. There they found provisions and water for thirteen days, one liter per person and day. On the third day after the wreck they lost part of the water from a sea stroke and at the end of the fifth day one of the men died.
Finally, the water lasted exactly what was expected. How much water was spilled?
Some of the data offered by the problem are irrelevant and paradoxically, the fact of not knowing the number of crew members traveling in the lifeboat is not important.
We know that after the fifth day, the deceased person would have consumed 1 liter of water daily for 8 days, so this was the amount of water spilled, 8 liters.