Answer:
Step-by-step explanation:
[tex]n(t)=100 e^{-.023t}[/tex]
when t = 3
[tex]n(3)=100 e^{-.023\times 3}[/tex]
[tex]n(3)=100 e^{-.069}[/tex]
= 93.33
when t = 8
[tex]n(8)=100 e^{-.023\times 8}[/tex]
[tex]n(8)=100 e^{-.184}[/tex]
= 83 .2
no of grams decayed = 93.33 - 83.2
= 10.13 grams
average rate of decay = 10.13 / ( 8 - 3 )
= 2.026 gm / year .
