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Half life of a radioactive substance is ...

Half life of a radioactive substance is 60 min. After 3 hours, the fraction of total number of atoms that have decayed would be

A

0.125

B

0.875

C

0.085

D

0.25

Text Solution

Verified by Experts

The correct Answer is:
b
No. of half likes=`(3xx60)/60=3`
`1-1/2-1/4-1/8,1-1/8=7/8xx100=87.5%`
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