Here's what I got.
Start by taking a look at the solubility graph for potassium nitrate,
As you can see, the graph indicates the mass of potassium nitrate that can be dissolved per
The green curve shows the amount of potassium nitrate that can be dissolved in
In other words, in a saturated solution, the rate at which the solid dissolves to produce ions in solution is equal to the rate at which the dissolved ions combine to reform the solid.
Now, start at
You should find that at
In your case, you have
#overbrace(" 95 g ")^(color(blue)("what you want to dissolve")) - overbrace(" 75 g ")^(color(blue)("what can be dissolved")) = overbrace(" 20 g ")^color(blue)("what remains undissolved")#
Therefore, your solution will contain