度與度、分、秒之間的轉化.
(1)把25.72°用度、分、秒表示;
(2)把45°12′30″化成度.
解:(1)∵25.72°=25°+0.72°,0.72゜=0.72×60′=43.2′,0.2′=0.2×60′=12″,
∴25.72°=25°43′12″;
(2)∵30″=0.5′,12.5′=12.5×(

)°=0.21°,
∴45°12′30″=45.21°.
分析:(1)將0.72°化為43.2′,再將0.2′化為12′′,繼而可得出答案;
(2)先將秒化為分,再將分化為度.
點評:本題考查了度分秒的換算,關鍵是掌握1°=60′,1′=60″.