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An unknown radioactive element decays into non-radioactive substances.
In ` 320` days the radioactivity of a sample decreases by `62` percent.
(a) What is the half-life of the element?
(days)
(b) How long will it take for a sample of `100` mg to decay to `47` mg?
(days)
Box 1: Enter your answer as a number (like 5, -3, 2.2172) or as a calculation (like 5/3, 2^3, 5+4)
Enter DNE for Does Not Exist, oo for Infinity
229.23807313784
Box 2: Enter your answer as a number (like 5, -3, 2.2172) or as a calculation (like 5/3, 2^3, 5+4)
Enter DNE for Does Not Exist, oo for Infinity
249.70154571736