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Stells [14]
3 years ago
14

college algebra - please help The half-life for thorium-227 is 18.72 days. The amount A (in grams) of thorium-227 after t days f

or a 10-gram sample is given by A(t)=10⋅0.5^t/18.72 How long will it take before 4 grams of thorium-227 is left in the sample? Round your answer to the hundredths place. ______days

Mathematics
1 answer:
Andreyy893 years ago
6 0

Answer:

t= 24.75 days

Step-by-step explanation:

Here A(t) is the amount of the element that remains after some time. So they tell us that find the time it takes to basically have 4 grams remaining so A(t) = 4

4 = 10 * 0.5 ^ (t/18.72)

0.4= 0.5 ^ (t/18.72)

t= 24.75 days

Answer should make sense because half life is around 18 days which means to go from 10 g to 5g would be somewhere around 18 days but we are going to 4 g so it takes more days

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