IF 80mg of a radioactive element decays to 10mg in 30 minutes, the halflife of this element is a.10 min b.20 min c.30 min d.40 min the answer is a.10 min but i would like to know why, please help.
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IF 80mg of a radioactive element decays to 10mg in 30 minutes, the halflife of this element is a.10 min b.20 min c.30 min d.40 min the answer is a.10 min but i would like to know why, please help.

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If there are 80 milligrams of a radioactive element decays to 10 milligrams in 30 minutes then what is the elements half life in minutes? Ok i narrowed it down to either 10 or 30...but im rly confused so if u could help it wuld be grea 80 40 1 min 20 2 min

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