Answer:
3:36 PM
Step-by-step explanation:
Let fraction (y) of the people that heard the rumor , the differential equation that is satisfied by the by y is,
Solving the differential equation,
The total number of inhabitants of the town = 2000
The number of people that heard the rumor = 160
At 8 AM, let t = 0,
= 0.08
By noon, half of the town as heard the rumor.
Then,
Therefore,
k ≈ 0.06106
Calculating time, t when y(t) = 90%
⇒ y(t) = 0.9
t = 7.59 hours
⇒ 7 hours 36 minutes
From 8 A.M. plus 7 hours 36 minutes = 3:36 PM
At 3:36 PM will 90% of the population have heard the rumor