$$P$$ can complete a job in $$12$$ days working $$8$$ hours a day. $$Q$$ can complete the same job in $$8$$ days working $$10$$ hours a day. If $$P$$ and $$Q$$ work together, working $$8$$ hours a day, in at least how many whole days can they complete the job? 
Overseas Competition->Knowledge Point->Word Problem Modules->Work Word Problems->Collaborative Work Word Problems