Question

The population of Cypress Lake is 7.2 times 10^4 residents. A surveyor determines that the average resident uses 2,900 gallons of water each year. The expression 2.088\ times 10^x represents the estimated total water usage by all Cypress Lake residents in one year. What is the value of x

I'm stumped when i use a calculator it comes out as infinity

Answer 1

So gallons of water = 7.2(10^4)(2900) or 208,800,000 gallons = 2.088(10^8)
this is also equal to 2.088(10^x)

So if 2.088(10^x) = 2.088(10^8)
clearly, x must be 8

notice, no calculator was really required other than (7.2)(10^4)(2900)