SOLUTION: The bacteria E Coli are found in the human bladder. Suppose 3,000 bacteria are present at time t = 0. Then, t minutes later the number of bacteria present can be approximated by

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Question 225935: The bacteria E Coli are found in the human bladder. Suppose 3,000 bacteria are present at time t = 0. Then, t minutes later the number of bacteria present can be approximated by N(t) = 3000(2)t/20.
How many bacteria will be present after 40 minutes?
How long will it take before there are 100,000 bacteria present?

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of:
N%28t%29+=+3000%282%29t%2F20
I think you meant:
.
N%28t%29+=+3000%282%29%5E%28t%2F20%29
.
If so,
then
How many bacteria will be present after 40 minutes?
.
N%28t%29+=+3000%282%29%5E%28t%2F20%29
.
N%2840%29+=+3000%282%29%5E%2840%2F20%29
.
N%2840%29+=+3000%282%29%5E2
.
N%2840%29+=+3000%284%29
.
N%2840%29+=+12000
.
How long will it take before there are 100,000 bacteria present?
Set N(t) to 100000 and solve for t:
.
N%28t%29+=+3000%282%29%5E%28t%2F20%29
.
100000+=+3000%282%29%5E%28t%2F20%29
.
100%2F3+=+%282%29%5E%28t%2F20%29
.
log%282%2C100%2F3%29+=+t%2F20
.
20%2Alog%282%2C100%2F3%29+=+t
.
101.18 minutes = t