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The half-life of a radioactive isotope X...

The half-life of a radioactive isotope `X` is `20 yr`. It decays to another element `Y` which is stable. The two elements `X` and `Y` were found to be in the ratio `1:7` in a sample of given rock. The age of the rock is estimated to be

A

40 yr

B

60 yr

C

80 yr

D

100 yr

Text Solution

Verified by Experts

The correct Answer is:
B
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