Question

A group of scientists studied the effect of a chemical on various strains of bacteria. Strain A started with 6000 cells and decreased at a constant rate of 2000 cells per hour after the chemical was applied. Strain b started with 2000 cells and decreased at a constant rate of 1000 cells per hour after the chemical was applied. When will the strains have the same number of cells? Explain.

Answer 1

After 3 hours each strain will have been depleted completely to 0 cells. Given the numbers 6000 and 2000, you will find that a decrease of 33.33333% for strain A and a 50% decrease for strain B will not intercept on the same hour. Strain B will have been depleted for an hour at the time that strain A is gone.