Contagious diseases can spread very quickly. Suppose five people are ill during the first week of an epidemic and that each person who is ill spreads the disease to four people by the end of the next week. By the end of the tenth week of the epidemic, how many people have been affected by the illness?

Question

jazzyfa30 · Answer

@mathcalculus

jdoe0001 · Answer

$\bf a_n = a_1+(n-1)d\
\text{so the 10th term/week will be}\
\large a_{10} = a_1+(10-1)d$

d = common ratio, in this case, each quantity of ill follks will infect 4 each, so  the common ratio is

5, 5*4, (5*4)*4, (5*4*4)*4 .....

is "4"

jdoe0001 · Answer

hmm, I got my equation mixed up, one sec, that's the wrong one :(

jdoe0001 · Answer

$\bf a_n = a_1r^{n-1}\
\text{so the 10th term/week will be}\
\huge a_{10} = a_1\times r^{(10-1)}$

r = common ratio

jazzyfa30 · Answer

?????

jazzyfa30 · Answer

@pengembara_bumi1

anonymous · Answer

use the formula given dear

jazzyfa30 · Answer

dont understand it or know how too fill it in