The amount of the radioactive material in the vault after 140 years is 210 pounds
We have that the function is given as a model;
f(x) = 300(0.5)x/100
Where
Let's substitute the value of 'x' in the model
f(x) = 300(0.5)x/100
[tex]f(x) = \frac{300(0.5) * 140}{100}[/tex]
[tex]f(x) =\frac{21000}{100}[/tex]
f(140) = 210 pounds
This mean that the function of 149 years would give an amount of 210 pounds rounded up to the nearest whole number.
Thus, the amount of the radioactive material in the vault after 140 years is 210 pounds
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