You can
put this solution on YOUR website!Your equation says:
#of bacteria at time "t" is n(t) = 3000(2)^(t/20)
By the way this means the number doubles every 20 minutes.
n(10)=3000 (2)^(10/20)
n(10)=3000 (2)^(1/2)
n(10)=3000 (sqrt 2)
n(10)=4242.64....
So you see you have to substitute 20 or 30 or 40 or 60 into
the formula in place of the "n".
Cheers,
Stan H.