Answer:
See explanation.
Step-by-step explanation:
Hello, your question is not very clear.
Based on the limited information, this is how we go about it.
If the rate at which people learn about a secret is directly proportional to the number of people who know the secret and 20 people know it on day 2, then the unit rate is 10.
That is the constant of proportionality is 10.
The direct variation equation is
[tex]y = 10x[/tex]
We want to find how long it will take take for a whole school population of 4000 people to know the secret.
We put y=4000 and solve for x.
[tex]4000 = 10x[/tex]
[tex]x = 400[/tex]
Hence it will take 400 days.
