Question
The half-life of a radioactive substance is 10 days. The
time in which only 1/8th of the original substance remains is:Solution
When only 1/8 of the substance remains, it means 3 half-lives have passed because: (1/2)³ = 1/8 Each half-life is 10 days, so total time = 3 × 10 = 30 days. Therefore, the correct answer is 30 days.
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