Camp has a total of 60 campers and 20 of the campers do not know how to swim. If the rest of the campers have mastered swim. If the rest of the campers have mastered swimming which statement is true?

For every 3 campers that knows how to swim. There is one camper that does not know how to swim
For every 2 campers that knows how to swim. There is one camper that does not know how to swim
For each camper that knows how to swim. There are two that do not know how to swim
For each camper that knows how to swim. There are three that do not know how to swim

The correct statement is: For every 3 campers that know how to swim, there is one camper that does not know how to swim.