The number of people in a town of 10,000 who have heard a rumor started by a small group of people is given by the following function: N(t)=10,000/5+1245e^-.97t

a. How many people were in the group that started the rumor?

b. How many people have heard the rumor after 1 day? After 5 days?

c. How long will it be until 1,000 of the people in the town have heard the rumor?

Question

The number of people in a town of 10,000 who have heard a rumor started by a small group of people is given by the following function: N(t)=10,000/5+1245e^-.97t


a. How many people were in the group that started the rumor?


b. How many people have heard the rumor after 1 day? After 5 days?


c.	How long will it be until 1,000 of the people in the town have heard the rumor?

anonymous · Answer

@satellite73 here :)

anonymous · Answer

need help with the last part?

anonymous · Answer

the second and last question

anonymous · Answer

you can do the second one (probably the third too) but the second one is a calculator exercise

anonymous · Answer

what do i put in the calculator?

anonymous · Answer

replace $t$ by $1$ you get this http://www.wolframalpha.com/input/?i=10%2C000%2F%285%2B1245e^-.97%29

anonymous · Answer

then replace t by 5 and get this http://www.wolframalpha.com/input/?i=10%2C000%2F%285%2B1245e^%28-.97*5%29%29

anonymous · Answer

so basically for number 1 i should say after 1 day about 21 people heard the rumor?

anonymous · Answer

yes

anonymous · Answer

okay and  678 for after 5 days :)
what about the last question?

anonymous · Answer

set that beast equal to 1000 and solve for $t$

anonymous · Answer

$$1000=\frac{10000}{5+1245e^{-.97t}}$$
$$5+1245e^{-97t}=10$$
etc

anonymous · Answer

what would the final answer be in that case?

anonymous · Answer

what would the final answer be in that case?

anonymous · Answer

@satellite73

anonymous · Answer

i got t=-2.1188 but i dont know how to find out the answer from here