This isn't as complicated as it looks.
1. If you have 10% solute, then you have 90% solvent because 90% + 10% = 100%..
2. If you have 20% solute, then you have 80% solvent because 80% + 20% = 100%.
3. The cell is hypotonic compared to the beaker because it has less solute inside of it. Usually people say the solution's tonicity and not the cell's tonicity though.
4. Because the cell has less solute than its environment, water will flow outside of the cell. Think of it as water flowing outside to "dilute" more concentrated areas. Water always flows from an area of low concentration to an area of high concentration to achieve equilibrium.
