What is the reason radioactive decay is measured in half-life’s instead of just using the elements “full-life”?

Question

Is there something special about the halfway point? Does the decay happen at a steady pace or exponentially?

In: 910

Answer 1

Every half life half of it goes away, so if you have 10lb, one half life gives you 5, a second half life gives you 2.5, next 1.25…. Goes on and on till it is theoretically gone.