If a 15.0 N force is applied to a level at a distance of 10.0 m from the fulcrum then how much force is needed at 25.0m from the fulcrum to balance the 15.0 N force?

Obviously, you want us to do your homework for you. That's a "No No". I think I'm done here.

Show us your work and we'll critique.

Find the anticlockwise and clockwise moments, from



The moments from both distances from the fulcrum have to be equal so that the system is balanced. So, equate your equations!