To find the approximate total number of cells in the three petri dishes, we can add the number of cells in each dish:
- First dish: 22,340 cells
- Second dish: 43,560 cells
- Third dish: 36,612 cells
Now, let's add them:
22,340 + 43,560 + 36,612 = 102,512
The closest response to this total among the options provided is 100,000.