The half-life of a radio isotope is 20 hours. After 60 hours, how much amount will be left behind [MP PMT 1991]

The half-life of a radio isotope is 20 hours. After 60 hours, how much

1.	The half-life of a radio isotope is 20 hours. After 60 hours, how much amount will be left behind [MP PMT 1991]
A.	1/8
B.	1/4
C.	1/3
D.	½
Answer» B. 1/4

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The half-life of a radio isotope is 20 hours. After 60 hours, how much amount will be left behind [MP PMT 1991]

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