Answer:
450 bacteria.
Step-by-step explanation:
To find this, we can set up an exponential equation as shown:
[tex]28800 = a (2)^{\frac{120}{20} }[/tex]
**'a' being the initial value
** '2' representing the culture doubling
Simplify the equation down:
[tex]28800 = a (2)^{6}[/tex]
[tex]28800 = 64a\\a = 450.[/tex]
Therefore, the initial amount of bacteria was 450.
