Solution.
The problem is an exponential growth problem (Because The number of cells in the tumor doubles every 2.5 months)
The formula for exponential growth is
In the problem given,
a = 1
r = 2
(i) After 2 years, that is ( 2 x 12 months = 24 months)
t = 24/2.5 = 9.6
[tex]\begin{gathered} f(9.6)=1(1+2)^{9.6} \\ =1(3)^{9.6} \\ =38050.822 \\ =38,050(nearest\text{ whole number\rparen} \end{gathered}[/tex]The number of cell that will be after 2 years = 38,050 cells (nearest whole number)
(ii) After 5 years
5 years = 5 x 12 months = 60 months
t = 60/2.5 = 24
[tex]\begin{gathered} f(24)=1(1+2)^{24} \\ =3^{24} \\ =282,429,536,481 \end{gathered}[/tex]