your baby brother has an ear infection. The doctor saud there are probably 50 000 000 bacteria in his left ear. The penicillin the doctor prescribed will k**l7% of the bacteria every hour. How many bacteria will be in you brother's ear in 1day,1week
1 day = 24 hour
After one hour there will be ((100-17)% = 83% = 0.83 of the original amount left
that is after 1 hour there will be
5*10^7 * 0.83
after 2 hours
\(5*10^7 * 0.83 * 0.83 = 5*10^7 * 0.83^2\)
after 3 hours
\(5*10^7 * 0.83 * 0.83 = 5*10^7 * 0.83^3\)
after 24 hours
\(5*10^7 * 0.83 * 0.83 = 5*10^7 * 0.83^{24}\)
5*10^7*0.83^24 = 571274 bacteria left
and you can do the 1 week question. How many hours are in a week anyway?