A 0.490-kg block is attached to a horizontal spring that is at its equilibrium length, and whose force constant is 25.0N/m . The block rests on a frictionless surface. A 6.00×10−2-kg wad of putty is thrown horizontally at the block, hitting it with a speed of 2.10m/s and sticking.

How far does the putty-block system compress the spring? (In other words what is X max)