# bacteria problem

• May 22nd 2010, 06:06 PM
alessandromangione
bacteria problem
the number of bacteria present in a culture after t minutes is given as B = 1000e^kt. if there are 3448 bacteria present after 7 min...find k
• May 22nd 2010, 08:16 PM
spruancejr
If B = number of bacteria, then you can solve the equation by plugging in the numbers you know and finding k. "e" is 2.718.....there is a button on scientific calculators which will give you the precise value of "e".
• May 22nd 2010, 09:00 PM
alessandromangione
so do i have to do like this? :
B/1000 et= k?
• May 22nd 2010, 09:12 PM
spruancejr
Quote:

Originally Posted by alessandromangione
the number of bacteria present in a culture after t minutes is given as B = 1000e^kt. if there are 3448 bacteria present after 7 min...find k

Your last sentence contains B and t. Use those to find k in your equation B = 1000e^kt

To reduce the powers of your equation, use a natural log function (ln)
i.e. to find k in the equation B = e^k take the (ln) of both side which yields ln B = k