N = a (2)^(t/20), where N is the number of bacteria, t is the number of minutes, a is the initial count, our problem.
counting 7:00 as zero time
and 5:00 am as t = 10 hrs = 120 minutes
1000000 = a(2)^(120/20)
1000000 = a(2)^6
64a = 1000000
a = 1000000/64 = 15625 of the germs
you could work backwards and cut the count in half 6 times
1,000,000 ---> 500,000
500,000 ---> 250,000
250,000----> 125,000
125,000----> 62,500
62,500 -----> 31250
31250 ---> 15625
You ingest a certain dangerous bacteria at dinner by accident. When more than 1,000,000 of these organisms are in your gut, you will become violently ill. Their population doubles every 20 minutes. You ate dinner at 7pm and by 5am you are sick. At least how many of these bacteria did you ingest at dinner?
1 answer
1 answer