Answer:
Initial bacterias = 6006000
Altought I believe is safe to assume that the values were 192,000 and 384,000 instead of 192,192,000 and 384,384,000, in that case the initial bacterias is 6000
Step-by-step explanation:
A exponential growth follows this formula:
Bacterias = C*rⁿ
C the initial amount
r the growth rate
n the number of time intervals
Bacterias (55 hours) = 192,192,000
Bacterias (66 hours) = 384,384,000

If you divide both you can get the growth rate:

So with that r = 2 and each time interval correspond to 11 years
Then replacing in one you can get the initial amount of C
