Question

In a village, the cases of a particular infectious disease have been exponentially decreasing at a rate of 80% per year since the people started receiving the vaccine. If there were 200 cases in the village to start with, predict the number of cases after 2 years.

Answer 1

Answer:

8

Step-by-step explanation:

Exponential decay is expressed by an equation of the form:

A = P(1 - r)^t

where P = initial value, r = annual rate of decay, t = time in years

A = 200(1 - 0.80)^2

A = 8