Respuesta :

[tex]\bf \textit{Amount for Exponential Decay using Half-Life} \\\\ A=P\left( \frac{1}{2} \right)^{\frac{t}{h}}\qquad \begin{cases} A=\textit{accumulated amount}\\ P=\textit{initial amount}\to &900\\ t=\textit{elapsed time}\to &148\\ h=\textit{half-life}\to &74 \end{cases} \\\\\\ A=900\left( \frac{1}{2} \right)^{\frac{148}{74}}\implies A=900\left( \frac{1}{2} \right)^2\implies A=225[/tex]

The amount that remained out of the 900 mg sample after 148 days is 225 milligrams.

Given,

Iridium -192 has a half-life of 74 days.

We need to find out after 148 days how many milligrams of the 900 mg sample will remain.

Here the initial amount is 900mg.

What is half life?

It is the time at which the initial amount of a substance is reduced to half its amount.

The formula used with half-life:

[tex]N_{t} =N_{0} (\frac{1}{2})^\frac{t}{t_\frac{1}{2} }[/tex]

Where

N_t = Amount after time t

N_0 = initial amount

t_1/2 = half-life value of the substance.

t = time.

We have,

N_0 = 900 mg

t_1/2 = 74 days.

t = 148 days.

Substituting the values in the formula,

We get,

N_t = 900 ( 1/2 ) ^148/74

N_t = 900 ( 1/2 )^2

N_t = 900/4

N_t = 225 mg

We see that the amount that remains after 148 days is 225 milligrams.

Thus the amount that remained out of the 900 mg sample after 148 days is 225 milligrams.


Learn more about half-life here:

https://brainly.com/question/3649113

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