A total of $$120$$ P1 and P6 students were asked to water some trees. Each P6 student carried $$2$$ buckets of water while $$2$$ P1 students carried $$1$$ bucket of water. There was a total of $$180$$ buckets of water. How many P1 students are there? (Each student only went to carry the bucket once) 
Overseas Competition->Knowledge Point->Word Problem Modules->Chicken-Rabbit Problems