Question

Rachel and marc were given the information shown below about the bacteria growing in a petri dish in their biology class. rachel wants to model this information with a linear function. marc wants to use an exponential function. which model is the better choice? explain why you chose this model.

Answer 1

The appropriate model depends on the growing conditions.

If growth is limited by nutrients that are supplied at a constant rate, then Rachael's (linear) model is a better choice. The rate of change of a linear function is a constant.

If growth is limited only by the number of bacteria present, then Marc's (exponential) model is the better choice. The rate of change of an exponential function is proportional to the value of the function.