According to the Momentum Conservation Principle:
For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. That is, the momentum lost by object 1 is equal to the momentum gained by object 2.
Lets say we have a 2 carts of a certain mass. We launch 2 balls of equal mass with equal speed, 1 into each cart, 1st made from plasticine ( inelastic collision), the 2nd made from rubber (elastic collision). Does it mean that a cart hit by rubber ball would have after an impact a greater speed?