The bacteria in a certain culture double every 7.3 hours. The culture has 7,000 bacteria at the start. How many bacteria will the culture contain after 4 hours ?

Question

amistre64 · Answer

hmm, if we knew the rate, we could determine the rest

A=Pe^rt

A/P = e^rt

ln(A/P) = rt

ln(A/P)
------ = r
     t


but since at t=7.3 we have that A = 2P

ln(2P/P)
------ = r
     7.3

amistre64 · Answer

ergo:

$$A=7000e^{\frac{ln(2)}{7.3}t}$$

calculate for t=4

anonymous · Answer

well these are  the answer options... 

A) 8,324 bacteria 

b) 10,234 bacteria 

c) 24,801 bacteria 

d) 7,697 bacteria

amistre64 · Answer

then im sure one of them will fit the bill

anonymous · Answer

is there any way you can make the equation you just did larger i cant see anything after the 7000

amistre64 · Answer

$$\Huge A=7000e^{\frac{ln(2)}{7.3}t}$$
thats about the best I can do to it :)

anonymous · Answer

thank you

amistre64 · Answer

yw, good luck :)

anonymous · Answer

one last thing .. what does the ln stand for

anonymous · Answer

natural logarithm, log with base e