precal
posted by Anonymous
A petri dish contains only two bacteria. The bacteria divide every half hour. How many bacteria will exist after 3 hours?
I thought it'd be 12, but apparently not.

Ms. Sue
1st hour: 2, 4
2nd hour: 8, 16
3rd hour: 32, 64 
BOSS
It divides 2 times every hour, so for 3 hours it'll divide 6 times. You start with 2, and every half hour they divide into 2. So that means they divide into 2 a total of 6 times. Soo, that's the original 2 times 2^6. So its 2*64 = 128

Gloria
A bacteria culture divide each half hour, after 3 hours there are
6400 bacteria, how many bacteria were there to begin with ?
Respond to this Question
Similar Questions

precalculus
A bacteria culture initially contains 1500 bacteria and doubles every half hour. a) Find an expression for the number of bacteria after t hours. Q(t)= b) The number of bacteria after 20 minutes is (the answer must be an integer) c) … 
Math
A culture of bacteria in a petri dish is doubling every hour. If there are 100 bacteria at time t=0, how many bacteria will there be in 12 hours? 
math
Bacteria is growing in a petri dish. Initially, there were 15,000 bacteria in the dish. It triples every 8 hours. Write the equation to represents this growth after t hours. 
calculus
a colony of bacteria living on a petri dish under optimal conditions doubles in size every ten minutes. At noon on a certain day, the Petri dish completely covered with bacteria. At what times (to the nearest hour, minute and second) … 
math
Five bacteria are placed in a dish and then counted each hour. The first three bacteria counts were 12, 26, 54. If the pattern continues, how many hours after the bacteria were placed in the dish will there be 222 bacteria? 
Algebra
At noon, Professor Simon has a petri dish with 10,000 cells of Bacteria A. In another petri dish, he has 33,000 cells of Bacteria B. Every hour, Bacteria A grows by 8%. Every hour Bacteria B cells die off, decreasing the number of … 
Math PLEASE HELP!!
At noon, Professor Simon has a petri dish with 10,000 cells of Bacteria A. In another petri dish, he has 33,000 cells of Bacteria B. Every hour, Bacteria A grows by 8%. Every hour Bacteria B cells die off, decreasing the number of … 
Math NEED HELP URGENT
At noon, Professor Simon has a petri dish with 10,000 cells of Bacteria A. In another petri dish, he has 33,000 cells of Bacteria B. Every hour, Bacteria A grows by 8%. Every hour Bacteria B cells die off, decreasing the number of … 
Honors Algebra
A biologist is researching a newly discovered species of bacteria. At time t=0 hours, she puts on hundred bacteria into a Petri dish. Six hours later, she measures 450 bacteria. Assuming exponential growth, what is the growth rate … 
Maths
The cells of a certain culture of bacteria double every 6 minutes. If there are 3 cells in a petri dish, how many cells of bacteria will htere be after on and a half hours?