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The mean lives of a radioactive substanc...

The mean lives of a radioactive substance are 1620 years and 405 years for `alpha` emission and `beta` emission respectively. Find out the time during which three fourth of a sample will decay if it is decaying both by `alpha`-emission and `beta`-emission simultaneously. `(log_e4=1.386).`

A

449 yrs

B

399 yrs

C

549 yrs

D

579 yrs

Text Solution

Verified by Experts

The correct Answer is:
A
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