Question

In the year 2019, Lee County used approximately 55 million gallons of water. Historical trends show that each year the water demand is increasing at a rate of approximately 2.1%. If this trend continues, approximately how many million gallons of water of water will be used by Lee County in the year 2025? Round to the nearest million.

Answer 1

To the nearest million, this is 62,000,000 gallons

Explanation:

Here, we are to calculate the amount of water expected to be used by Lee County in the year 2025.

To calculate this amount, we set up an exponential function as follows;

A = I(1+r)^t

where A is the amount expected in the year 2025

I is the initial amount of water used which is 55 million

r is the percentage change per year which is 2.1% or simply 2.1/100 = 0.021

T is the difference in the years between 2025 and 2019 = 2025-2019 = 6 years

Plugging these values into the equation, we have

A = 55,000,000(1 + 0.021)^6

A = 55,000,000(1.021)^6

A = 62,304,173.899295434

To the nearest million, this is 62,000,000 gallons