Answer: The population after 3 hours is 13.9 mill.
Step-by-step explanation:
When we have an exponential with:
A = initial population.
r = constant relative growth rate:
t = time.
The function that models this is:
P(t) = A*e^(k*t)
In this case we know that:
A = 3.9 mill.
r = 0.4225 1.
Then the function that models the population of this yeast cell is:
P(t) = (3.9 mill)*e^(0.4225*t)
where t represents the time in hours.
Then if we want to know the population after 3 hours, we should replace t by 3.
P(3) = (3.9 mill)*e^(0.4225*3) = 13.85 mill.
And we want to round our answer to one decimal place, then we must look at the second decimal place, we can see that is a 5, so we should round up.
The population after 3 hours is 13.9 mill.