Here it says label the tonicity of the solution outside the cell where the dot, the purple dot, are these solute particles. Right. So what we have to do is we have to look at how many dots we have on the outside, and compare it to the number of dots on the inside. In the first image, we can see that inside the cell is more concentrated. Outside the cell is less concentrated, it has fewer purple dots. Remember, we have to discuss what type of solution is on the outside. Since the outside is less concentrated, it is a hypotonic solution.

For the second one, both the inside and the outside have 5 purple dots, so 5 solute molecules. They're equal inside and out. So, this would have to be an isotonic solution.

And then finally here we have the outside having more dots. So the outside is more concentrated. Since the outside is more concentrated, this represents a hypertonic solution. So, just remember, we're looking at what the solution is on the outside relative to what's inside a particular cell.