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Cobalt-60 has a half-life of 5 years. After 20 years, what percent of the original sample would remain?
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Cobalt-60 has a half-life of 5 years. After 20 years, what percent of the original sample would remain?

User Chathuri Fernando
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1 Answer

3 votes

Answer:

6.25%

Step-by-step explanation:

20/5=4

half-life=1/2 of previous life

1/2=50%

50%=0.5

(0.5)^4 = ==> get the 4 from dividing total years(20) by the half-life(5): 20/5

0.0625

0.0625*100%=6.25%

User Marcosdsanchez
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