Half-lives of two radioactive elements A and B are 20 minutes and 40 m – McqOptions

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1.	Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes, respectively. Initially, the samples have equal number of nuclei. After 80 minutes, the ratio of decayed number of A and B nuclei will be:
A.	\[1:4\]
B.	\[5:4\]
C.	\[1:16\]
D.	\[4:1\]
Answer» C. \[1:16\]

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