Sangeetha Pulapaka

The formula for exponential growth is

y = a(1+r)^{t}

where a is the initial amount, r is the rate of increase expressed as a decimal, t is the time elapsed, and y is the final amount.

Plug in 33,000 mega liters for the initial amount, 0.1 for the rate of increase, and 18 years for the time elapsed.

y = a(1 + r)t

y = 33,000(1 + 0.1)18

y = 33,000(1.1)

y ≈ 33,000(5.5599173)

y ≈ 183,477.2709

Round to the nearest hundredth.

183,477.2709 → 183,477.27

To the nearest hundredth, Stafford will use 183,477.27 mega liters of water annually.

Skills to further recall:

What is exponential growth and exponential decay

What is an exponential function

How to calculate a value to the nearest hundredth