Concept explainers
Epidemic outbreak. The number of people in a community who became infected during an epidemic r weeks after its outbreak is given by the function
where 20,000 people of the community are susceptible to the disease. Assuming that 1000 people were infected initially and 8999 had been infected by the end of the fourth week.
a. Find the number of people infected after 8 weeks.
b. After how many weeks will 12.400 people be infected?
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