Chapter 5.1, Problem 3E

Special Rounding Instructions When you perform logistic regression, round the $r$ value to three decimal places and the other parameters to two decimal places. Round all answers to two decimal places unless otherwise indicated.

Multiple Myeloma is a cancer of the blood plasma cells. One study used a logistic function to model the number $N$, in billions, of cells in a myeloma tumor $t$ days after the typical size at diagnosis:

$N=\frac{1000}{1+999e^{-0.0114t}}$.

a. Plot the graph of $N$ versus $t$ over the first $1200\text{ days}$.

b. How long does it take the tumor to reach $100$ times its size at the time of diagnosis?