Ordinarily, you would rotate the protractor so the 0° mark lines up with one of the sides of the angle you want to measure. You have not done that here, but you can still find the measure of the angle.
Subtract the smaller scale value from the larger one to find the angle measure:
∠LMN = 180° -90° = 90°
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<em>Additional comment</em>
Most physical protractors are marked with two scales. One goes counterclockwise, as this one does. The other goes clockwise. At each point on the scale, the markings total 180°.
