Answer: 0.12
Step-by-step explanation:
An exponential decay can be written as:
C(t) = A*r^t
Where A is the initial amount of cookies, A = 100
r is the rate that we are searching.
t is time in minutes, we know that at t= 0m
C(0) = 100*r^0 = 100
so at t = 0m we have 100 cookies.
now, we know that at t = 15m we have.
C(15s) = 100*r^(15m) = 15
r^15 = 15/100 = 0.15
r = (0.15)^(1/15) = 0.88
So the rate at which the cookies decrease is 0.88, and 1 - r = 0.12 is the rate at which the kids eat the cookies (meaning that the students ate 12% of the cookies per minute), so the answer is 0.12
