换度分秒.45.6°= 78.43°= 用度表示.57°18′= 43°24′48″≈

45.6°=45°36′
78.43°=78°+0.43*60′=78°+25′+0.8*60′′=78°25′48′′
57°18′=57°+18*(1/60)°=57.3°
43°24′48′′
=43°+(1/60)°*24+(1/3600)°*48
≈43°+0.24°+0.013°
=43.253°
90°-17°50′
=89°-17°+60′-50′
=72°10′
15°24′×5
=75°+120′
=77°
31°42′÷5
=6°+102′/5
≈6°+20′
=6°20′
180°-（35°18′+62°56′4″)
=180°-(97°+74′+4′′)
=180°-98°14′4′′
=179°-98°+59′-14′+60′′-4′′
=81°45′56′′