Question

A Bacteria has a doubling period of 8 days. If there are 2250 bacteria present now, how many will there be in 33 days?
find the growth rate (Round this to 4 decimal places).
Growth Rate___________.
There will be _________ Bacteria.

I came up with:.0668 for the growth rate (I also put in 8.6643%)
and 72000 for the bacteria.
none of them are correct.

Answer 1

Since it grows by a factor of 2 every 8 days, the population is

2250 * 2^(t/8)
In 33 days there will be 39258

The growth factor for each day is 2^(1/8) = 1.0905, for a 9.05% per day growth rate

Answer 2

OK .. thanks .. the 39258 is correct. but the 1.0905 is showing as incorrect.