4.4.2.3 Half-lives and random decay

Spec reference: 4.4.2.3 (HT-only element).

Triple-only content in this dot

• Calculate net decline as a ratio after a given number of half-lives.
• Use repeated halving (or doubling backwards) for activity/count-rate.

Exam quick-check

• Can I identify this as a triple-only point from wording in the question?
• Can I apply the correct equation/idea with units and a clear conclusion?