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Iodine-125 has a half-life of about 60 days.

How many milligrams of a 500 mg sample will remain after 300 days?

1. 0.6 mg
2. 7.8125 mg
3. 15.625 mg
4. 31.25 mg

2 Answers

4 votes

Answer:

Explanation:

15.625

User Manuel Otto
by
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2 votes
We know that Iodine - 125 has a half life of 60 days.
300 : 60 = 5 . It means that it was halved 6 times.
Therefore: 500 mg * 0.5^5 =
= 500 mg * 0.5 * 0.5 * 0.5 * 0.5 * 0.5 =
= 500 mg * 0.03125 = 15.625 mg
Answer: 3. 15.625 mg.
User Pkerckhove
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8.3k points