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Bismuth-210 has a half-life of about 5 days. After 15 days, how many milligrams of a 600 mg sample will remain?

User TastyWheat
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Every 5 days the number is cut in half. So from 600 mg to day 5, the sample will be 300 mg. Then from day 5 to day 10, the sample will reduce to 150 mg. And finally, from day 10 to day 15, the sample will have reduced to:

75 mg

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User Arpit Kulsreshtha
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Answer:

75 milligrams.

Explanation:

We have been given that Bismuth-210 has a half-life of about 5 days.

To solve our given problem we will use half-life formula.


y=a\cdot((1)/(2))^{(t)/(b)}, where,

a = Initial value,

t = Time,

b = half-life.

Upon substituting our given values in above formula we will get,


y=600\cdot((1)/(2))^{(15)/(5)}


y=600\cdot(0.5)^(3)


y=600\cdot 0.125


y=75

Therefore, 75 milligrams of Bismuth-210 will remain after 15 days.

User Harsh Pamnani
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