MHB How to Calculate the Remaining Mass of a Radioactive Substance Over Time?

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The discussion focuses on calculating the remaining mass of a radioactive substance with an initial mass of 300mg and a half-life of 2 years. The equation to model the mass over time is A = 300 * 2^(-t/2). After 12 years, the calculation shows that the remaining mass is 4.6875mg, which is confirmed to be correct. It is emphasized that the final answer should include the appropriate units. The importance of clarity in presenting the results is highlighted.
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Basically need more help checking my answers, I think it's better if I provide the full context:

A radioactive substance with an initial mass of 300mg has a half-life of 2 years.

a) Write an equation to model the mass of the material over time.

Let A = mass of the material
Let t = time

A = 300*2^(-t/2)

b) What mass will remain after 12 years?A = 300*2^(-t/2)
A = 300*2^(-12/2)
A=300*2^(-6)
A=300*1/2^6
A=300*1/64
A=75*1/16
A=75/16
A=4.6875
 
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That answer is numerically correct, but you should state the units: A=4.6875mg.
 
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