Solution: To create 32 cells, Escherichia coli cells must go through 5 division cycles, resulting in ${{2}^{5}}=32$ cells.  1→ 2 →4 →8 →16 →32 cells.

Each cycle takes 20 minutes to complete. As a result, the total time needed for 5 cycles is 20 X 5 = 100 minutes. It takes 100 mins.