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A radio isotope X with a half life 1.4xx...

A radio isotope `X` with a half life `1.4xx10^(9)` yr decays of `Y` which is stable. A sample of the rock from a cave was found to contain `X` and `Y` in the ratio `1:7`. The age of the rock is

A

`1.96 xx 10^(9) yr`

B

`3.92 xx 10^(9) yr`

C

`4.20 xx 10^(9) yr`

D

`8.40 xx 10^(9) yr`

Text Solution

Verified by Experts

The correct Answer is:
C
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