Question

Under ideal conditions, the number of ecoli bacteria can double every 20 minutes. This behavior can be modeled by the exponential function N(t)=Nzero(2^0.05t)
where t is the time in minutes andNzero is the initial number of bacteria.
A) if the initial number of bacteria is 2, how many will be present in 4 hours?

Answer 1

N{0} = 2; and t=4, we can googlize the equation and itll pop out an answer :)

Answer 2

2(2^(.05*4))= 2.29739671

http://www.google.com/search?aq=f&sourceid=chrome&ie=UTF-8&q=2(2^(.05*4))

Answer 3

might have to present t in minutes tho right?

Answer 4

3 sets of 20min per hour; 4 hours then equals 12 cycles

Answer 5

do you change the time to minutes, or leave it in hours?
because it is telling me the correct answer is 8,192

Answer 6

we were typing at the same time :-)

Answer 7

i believe you change it to minutes

Answer 8

let me see if I can work up a better looking formula ; or at least verify theirs

Answer 9

4 = 2e^(k*20)

ln(4/2)
------ = k
20

Answer 10

aha! thank you.

Answer 11

i get a rate of .03466

Answer 12

but im gonna brute math it :)

a{t} = amount
a{0:00} = 2
a{0:20} = 4
a{0:40} = 8
a{1:00} = 16
a{1:20} = 32
a{1:40} = 64
a{2:00} = 128
a{2:20} = 256
a{2:40} = 512
a{3:00} = 1024
a{3:20} = 2048
a{3:40} = 4096
a{4:00} = 8192

Answer 13

A = 2e^((ln(2)/20)*240) = 8,191.99999....