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50% of a radio active substance decays i...

`50%` of a radio active substance decays in `5` hours. The time required for the `87.5%` decays is

A

10 hours

B

15 hours

C

`12.5` hours

D

`17.5` hours

Text Solution

Verified by Experts

The correct Answer is:
B
`W = (W _(0))/(2 ^(n)) n = (t)/(t _((1)/(2)), t_(1//2) = 5 hrs`
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