Question

A drug that it will decrease the bacteria cells by 5% every hour. If you start with 1500 bacteria cells, how many will be present after 8 hours?

(I need this written as a y= equation)

Answer 1

after 8 hours there are 995 bacteria cells left

let y be the amount after 8 hours

the multiplying factor is 100 - 5 = 95 % = 0.95

y = 1500 × $(0.95)^{8}$ = 995