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A disease has hit a city. The percentage of the population infected t days after the disease arrives is approximated by ​p(t)equals8 t e Superscript negative t divided by 11 for 0less than or equalstless than or equals44. After how many days is the percentage of infected people a​ maximum? What is the maximum percent of the population​ infected?

A. The percentage of infected people reaches a maximum after__ days.


B. The maximum percent of the population infected is __%.

User Johannix
by
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1 Answer

3 votes

Answer:

A 11 days

B. 32.37%

Explanation:


p(t) = 8te^(-t/11)

percentage of infected people a maximum when p '(t) = 0

==>
p '(t) = 8(1)e^(-t/11) +8te^(-t/11)(-1/11)

==>
p '(t) = e^(-t/11)(8 -8t/11) </p><p> now, p '(t) = 0 </p><p>==> [tex]e^(-t/11)(8-8t/11) = 0 </p><p> ==>8 -8t/11 = 0 </p><p> ==> t = 88/8 = 11 days </p><p> Hence percentage of infected people reaches maximum after 11 days </p><p> maximum percent of the population infected = p(11) </p><p> ==> [tex]p(11) = 8(11)e^(-11/11)

==> p(11) = 88/e = 25.752 %

=32.37%

User Washery
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