The half-life of a radioactive sample is 2 hours. What fraction remains after 6 hours? MCQ with Answer and Explanation

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The half-life of a radioactive sample is 2 hours. What fraction remains after 6 hours?

A. 1/8

B. 1/16

C. 1/2

D. 1/4

Answer: Option A

Solution (By JKSSB Mock Tests)

Number of half-lives = 6/2 = 3. Remaining = (1/2)³ = 1/8. After each half-life, half the remaining decays.

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Correct Answer: Option C

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