The half-life of radium-222 is approximately 38 seconds.

Last updated: 7/29/2022

The half-life of radium-222 is approximately 38 seconds. Step 1 of 3: Determine a so that A(t)=A0a^t describes the amount of radium-222 left after t seconds, where Ao is the amount at time t = 0. Round to six decimal places. Answer How to enter your answer (opens in new window)