Question

what is the probability that a radioactive nucleus will not have decayed after a time equal to twice its Half Life​

Answer 1

Answer:

100% Probability  

(25 % as 25%  radioactive nucleus would be still there)

Explanation:

what is the probability that a radioactive nucleus will not have decayed after a time equal to twice its Half Life​

100% Probability  , That it will not decay after a time equal to twice its Half Life​

Let say radio active was = 100

after first Half Life​ time it will remain = 100 - 100/2 = 50

after second Half Life​ time it will remain = 50 - 50/2 = 25

25  % Radioactive will still be there after a time equal to twice its Half Life​

so there is 100 % probability that a radioactive nucleus will not have decayed

or if we  calculate on based of remaining then

25%  ( 25%  radioactive nucleus would be still there)