Word problem help

Question

Suppose the function
N = P 

1 − e^(−0.4t)

is used to model the length of time t (in hours) it takes for N people living in a town with population P to hear a news flash. How many people in a town of 40,000 will hear the news between 1 and 2 hours after it happened? (Round your answer to the nearest whole number.)

Answer 1

You need to evaluate the function at 2 hours and 1 hour and take the difference between the function values, that is the answer to this question is N(2) - N(1) 

 

If the function is N = P(1 - e^(-0.4t)) then 

 

N(2) = P(1 - e^(-0.8)) = P(1 - 0.449329) = 40000*0.550671 = 22027 

 

N(1) = P(1 - e^(-0.4)) = p(1 - 0.670320) = 40000*0.32968 = 13188 

 

So N(2) - N(1) = 22027 - 13188 = 8839