The figure shows a right triangle with acute angle of 27°, this angle is the angle between the water level and the ski ramp.
It is also shown the suplementary angle 27° marked as X°, which is the angle that you must determine.
In the figure is clear that x is the exterior angle of the corner with the angle of 27° and that X° + 27° = 180°.
Then you can solve for X.
X = 180° - 27° = 153°.
Answer: 153°
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