math problem solving bacterial growth?

Question

the doubling period of a bacterium is 20 mins. If there are 300 bacteria in a culture initially, how many bacteria will be there be after in 1 hour?

Answer 1

Apply the formula:

A = P x 2^(t/h)
where A = total population
P = initial population
h = doubling cyle/period
t = time elapsed

The answer for this Q would be 2400

Answer 2

The bacteria will double 3 times in one hour.

300 * 2 * 2 * 2 = 2400 bacteria