### Home > INT2 > Chapter 10 > Lesson 10.1.3 > Problem 10-43

The bacteria on Bailey’s petri dish are doubling in area every ^{^2}, then ^{^2}, then ^{^2}, then ^{^2}, etc. The science teacher asks Bailey’s team to predict the area that will be covered by bacteria after two hours.

Each team member writes a different expression for his or her prediction. Bailey writes

. Carmen writes . Demetri writes . Explain what the numbers in each expression mean in terms of the situation. What area will be covered by bacteria after two hours? is the starting number of bacteria. Bailey’s expression shows that the bacteria multiply by (every minutes), and because there are six -minute periods in two hours, the multiplier needs to be applied times. Carmen’s expression shows that the number of bacteria will multiply by per minute, and there are minutes in two hours. Demetri’s expression shows that the number of bacteria will multiply by every hour during the two-hour period. There will be bacteria after two hours. Now Bailey’s team has to determine the area that would have been covered by bacteria

minutes *before*they started the experiment. Write two different expressions that represent this situation and then determine the answer.sq. cm

What are two expression that give this answer?