A lawyer has determined that the number of people P(t) in a city of 1.2 million people who have been exposed to a news item after t days is given the function
P(t)=1,200,000(1-e^-0.03t)
a: How many days till 40% of the population has heard the news report?
b:After how many days will 80% of the population have heard the crime?

Question

A lawyer has determined that the number of people P(t) in a city of 1.2 million people who have been exposed to a news item after t days is given the function 
P(t)=1,200,000(1-e^-0.03t)
a: How many days till 40% of the population has heard the news report?
b:After how many days will 80% of the population have heard the crime?

campbell_st · Answer

ok... so what number of the population hasn't hear

for (a)   find 60% of 1 200 000  that will be P(t)  

substitute it and solve for t. 

(b) find 20% of 1 200 000 and then solve for t