Question

A colony of bacteria is growing exponentially according to the function below, where t is in hours. About how many hours will it take for the population to reach 400?
B(t)=4*e^0.8t
A-12
B-18
C-24
D-6

Answer 1

Looks like D is the closest

Answer 2

4*e^0.8t = 400
e^0.8t=100
ln (e ^ 0.8t) = ln (100)
0.8t * ln (e) = ln (100)
0.8t * 1 = ln (100)
t = ln(100) / (0.8) = 1.25 * ln (100)
t= 1.25 * 4.6
.: t=5.75≈6

Answer 3

Thank you so much!

Answer 4

My Pleasure.

Answer 5

Welcome to Openstudy.

Answer 6

Medal?

Answer 7

Can I get a medal?

Answer 8

@Nurali I need the medal more than you do.. lol