How would I approach this problem? I’m not sure how to solve measurements

To identify the mass of the solute, subtract the total mass by the mass of the graduated cylinder.
Thus, we have the following:
[tex]20.6g-2.55g=18.05g[/tex]To obtain the concentration of the solution, divide the obtained mass by the total volume and then simplify.
Thus, we have the following:
[tex]\frac{18.05g}{74.79mL}=\frac{1805g}{7479mL}\approx0.241g\cdot mL^{-1}[/tex]