Given:
The initial mass of an element is 800 grams.
Decay rate = 8.2% per day
Number of days = 15
To find:
The remaining element after 15 days.
Solution:
The exponential decay model is
[tex]y=a(1-r)^t[/tex]
Where, a is the initial value r is the rate of interest and t is time period.
Putting [tex]a=800,r=0.082,t=15[/tex] in the above formula, we get
[tex]y=800(1-0.082)^{15}[/tex]
[tex]y=800(0.918)^{15}[/tex]
[tex]y=221.68188[/tex]
[tex]y\approx 221.7[/tex]
Therefore, the mass of the remaining element is 221.7 grams.