A teacher is marking the papers of the whole class. She plans to finish the work in $5$ hours. After working for one hour, she finds that if she wants to finish the work as planned, she needs to mark $6$ more papers per hour. But if she can mark $10$ more papers per hour, she can even finish marking all the papers $1$ hour earlier. How many papers does she need to mark in total?                   
Overseas Competition->Knowledge Point->Word Problem Modules