500
The acute angles of right Δ ABC with AC = 3 meters, BC = 4 meters, AB = 5 meters, that is needed by a tile-setter so he can cut tiles precisely for the hypotenuse-edge of the floor.
What is m ∠ B ≈ 37 {from tan B = 3/4, or cos B = 4/5, or sin B = 3/5} and m ∠ A ≈ 53 (from tan A = 4/5, cos A = 3/5, and sin A = 4/5)