Question

Exponential model. Further research of the new disease has confirmed that its spread is

not linear, but exponential. Experts have estimated it to double every 7 days when it is
first introduced to a population.
Suppose there were 3 cases reported on the morning of day 1 of the outbreak. How many
cases will there be by the end of day 21?

Answer 1

Since the disease doubles every 7 days, the number of cases on day 21 will be 2^3 times the number of cases on day 14, which will be 2^2 times the number of cases on day 7, which will be 2^1 times the number of cases on day 1.

Starting with 3 cases on day 1, we can use the formula:

N = 3 * 2^(t/7)

where N is the number of cases after t days.

Plugging in t = 21, we get:

N = 3 * 2^(21/7) = 3 * 2^3 = 24

Therefore, there will be 24 cases by the end of day 21.

Explanation: