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Question
Consider a quantity of a radioactive substance. The fraction of this quantity that remains after t half-lives can be found by using the expression 3–t. What fraction of substance remains after 7 half-lives?
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Solution
Since, 3–t expression is used for finding the fraction of the quality that remains after t half-lives.
Hence, the fraction of substance remains after 7 half-lives will be equal to 3–7 i.e., `1/3^7`.
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