Concept explainers
Epidemiology A flu epidemic is spreading through a town of 48,000 people. It is found that, if x and y denote the numbers of people sick and well in a given week, respectively, and if s and w denote the corresponding numbers for the following week, then
(a) Write this system of equations in matrix form.
(b) Solve the resulting matrix equation for
(c) Suppose that 13,000 people are sick in a given week. How many were sick the preceding week?
(d) Same question as part (c), except assume that 14,000 are sick.
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