How Does Time Affect the Radioactivity of Substances with Different Half-Lives?

[cheetean]

Question:
A sample of radioactive substance K and a sample of another radioactive substances L have the same initial activity. the half life of K is TK and the half life of L is TL. After a time T, the activity of K was half the activity of L. Expression in term of T, TK, and TL.

 

[SammyS]

Question:
A sample of radioactive substance K and a sample of another radioactive substances L have the same initial activity. the half life of K is TK and the half life of L is TL. After a time T, the activity of K was half the activity of L. Expression in term of T, TK, and TL.

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