How much weight should I be able to lift?

I don’t recommend a 1 RM lift but there are calculations that can predict your 1 Rep Max lift by how many reps e.g. If I can do 12 reps at 112 lbs, this equates to a 1RM of 160 Lbs.

In other words if I can 1RM 160 lbs I should be able to do 10 reps 120 lbs.