Question

The chlorine concentration should remain between 1.5 and 2.5 parts per million (ppm) for safe swimming. After a warm, sunny day only 80% of the chlorine may remain in the water, with the other 20% dissipating into the air or combining with chemicals in the water. Let f(t)=3(0.8)^t model the concentration of chlorine in parts per million after t days. What is the initial concentration of chlorine in the pool? Will the chlorine ever be zero? When/Why?

Answer 1

3; no; none of the factors go to zero

Answer 2

Thank you. I thought it was 3.

Answer 3

at t = 0; .8 = 1; 3(1) = 3`