Warm up problem 11: easy Population growth

It is a exponential growth in the form of $x=a{ r }^{ n }$ where r is the growth rate, a is the starting population, and x is the population after n time units.

Take a as one so that triple the population is three such that:

$3=1({ 2 }^{ n })$

$\log { 3 } =n\log { 2 }$

$n=\frac { \log { 3 } }{ \log { 2 } }$

so the time it would take to triple the population is $\frac { \log { 3 } }{ \log { 2 } }$ time units.