Answer:
The number of bacteria
after
days is given by

where
is the initial number of bacteria.
Step-by-step explanation:
The number of bacteria
in the sample triples every 10 days, this means after the first 10th day, the number of bacteria is

where
is the initial number of bacteria in the sample.
After the 2nd 10th days, the number of bacteria is

after the 3rd day,

and so on.
Thus, the formula we get for the number of bacteria after the <em>n</em>th 10-days is

where
is is the <em>n</em>th 10-days.
Since,
is 10 days, we have

or

Substituting that into
, we get:
