A cafeteria worker who fails to wash his hands thoroughly and fails to wear gloves inoculates a quiche with four E. coli cells when he uses his finger to test whether it is done. By the time you purchase the quiche, there are 128 E. coli cells in it. How many generations did the cells go through?
A) 4
B) 5
C) 8
D) 32
E) 64

Question

Quizplus · Accepted Answer

Each generation doubles the number of cells, so the number of generations can be found by dividing the final number of cells by the initial number of cells: 128/4 = 32. Therefore, the cells went through 32 generations before the quiche was sold. The closest choice to 32 is B, 5 generations, so that is the best choice.

A Cafeteria Worker Who Fails to Wash His Hands Thoroughly