Half lives of two radioactive substances A and B are respectively 20 m – McqOptions

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1.	Half lives of two radioactive substances A and B are respectively 20 minutes and 40 minutes. Initially the sample of A and B have equal number of nuclei. After 80 minutes, the ratio of remaining number of A and B nuclei is [CBSE PMT 1998; JIPMER 2000]
A.	1 : 16
B.	4 : 1
C.	1 : 4
D.	1 : 1
Answer» D. 1 : 1

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