Question

The cells of a bacteria double in every 30 minutes. A scientist begins with a single cell. How many cells will be there after 12 hours.

Answer 1

12 hours  = 12 * 60 mins = 720 mins

Cells double  in every 30 mins

Therefore 720/30 = 24 cells

Answer 2

After 30 minutes there will be 2 cells

3 cells in one hour

3×12=36

Therefore there will be 36 cells after 12 hours