Oxford currently generates 45,000 tons of garbage per year. but the city is launching some recycling initiatives to bring that number down. If as a result, the amount of garbage decreases by 5% each year. Is this problem exponential growth or decay? Identify the growth or decay factor.

growth, (1 + .05)
growth, (1-.05)
decay,(1+.05)
decay,(1-.05)

Respuesta :

Answer:

-Exponential Decay

-Decay factor is (1-0.05)

Step-by-step explanation:

-Given that the number decreases by a defined rate each year from the initial size by 5%,

-This is an exponential decay function of the form:

[tex]y=Ae^{-rt}[/tex]

Where:

[tex]y[/tex] is the quantity/size after time t

[tex]A[/tex] is the initial size

[tex]r[/tex] is the rate of decay

-Our function can the be written as

[tex]y=45000e^{-0.05t}[/tex]

Hence, the decay rate/factor is 0.05

#Alternatively

The exponential decay can be of the form:

[tex]y=ab^x[/tex]

Where:

y is the size at time x, a is the initial size, x is time and b is the decay factor.

b is of the form [tex]b=(1-r),\ \ r=decay\ rate[/tex]

[tex]y=ab^x\\\\y=45000(1-0.05)^x[/tex]

Hence, the decay factor is (1-0.05)