Geometric series

the number of bacteria in a culture triples every 3 hours. if there were 2 bacteria present at noon one day, how many were there at noon the next day assuming that all bacteria survived?

 

First term =2

Ratio =3

Number of terms =24/3 =8, Therefore in 24 hours, you would have:

=6,560 bacteria.

This is also a geometric series. Use the well-known formula:

 

S=2(1 - 3^8) / (1 - 3)

2 x 3,280

S=6,560 bacteria in 24 hours.