Question

A township office estimates that the amount of trash on a road grows exponentially at a rate of 40% per month if it is not cleaned up. The township also estimates that there are 300 pounds of trash on its main road.

Enter the number of pounds of trash after 3 months.
____ Pounds

Answer 1

900

Explanation:

If 40% per month = 300. Multiply 300 by 3.

Answer 2

823 pounds of trash. ( approx )

Explanation:

Since, the exponential growth function is,

`A=P(1+r)^t`

Where,

P = initial value,

r = growth rate per period,

t = number of periods,

Here, P = 300 pounds, r = 40% = 0.4, t = 3 months,

Thus, the quantity of trash after 3 months,

`A=300(1+0.4)^3=300(1.4)^3 = 823.2\approx 823\text{ pounds}`