Question

A population of amoebas in a petri dish will triple in size every 20 minutes. at the start of experiment the population is 800.

Answer 1

If we are to derive the equation that models the growth of the amoeba, we make use of the general form:
p = po k^t
where po is the initial population
k is the multiplicative rate of change

From the problem
3po = po k^(20)
k = 1.06

The equation is
p = 800 (1.06)^t