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Half lives of two isotopes X and Y of a ...

Half lives of two isotopes X and Y of a material are known to be `2xx10^(9)` years and `4xx10^(9)` years respectively if a planet was formed with equal number of these isotopes, then the current age of planet, given that currently the material has `20%` of X and `80%` of Y by number, will be:

A

`2xx10^(9)" years"`

B

`4xx10^(9)"years"`

C

`6xx10^(9)" years"`

D

`8xx10^(9)"years"`

Text Solution

Verified by Experts

The correct Answer is:
D
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