Respuesta :
A=Pe^(rt)
P = 800g
t = 8 years
A = 450g
r = This is what we will try and find to start with
450=800e^(r*8)
After running the math through a calculator, we end with r = -0.07192
Now we just re-input this information into our equation: A=800e^(-0.07192*16)
A=800e^(1.15072)
Now we will re-write the equation using the negative exponent rule:
A = 800 1/e^1.15072
Combine right side:
A = 800/e^1.15072
Then do the math:
A = 253.12709836......
That will give us A = 253 (rounded to the whole number)
I hope this helps! :)
The substance that should be presented after 16 years is 253.
Given that,
- If 800g of a radioactive substance are present initially and 8 years later only 450g remain.
Based on the above information, the calculation is as follows:
We know that
[tex]A=Pe^{rt}[/tex]
Here
P = 800g
t = 8 years
A = 450g
[tex]450=800e^{r\times 8}\\\\A=800e^{-0.07192\times 16}\\\\A=800e^{1.15072}\\\\A = 800 \ 1 \div e^{1.15072}\\\\A = 800\div e^{1.15072}[/tex]
A = 253
Therefore we can conclude that the substance that should be presented after 16 years is 253.
Learn more: brainly.com/question/16115373