(31°40′-25°4′30〃)×3+28′3〃×2等于多少

问题描述:

(31°40′-25°4′30〃)×3+28′3〃×2等于多少

(31°40′-25°4′30〃)×3+28′3〃×2
=6°35′30〃×3+56′6〃
=19°46′30〃+56′6〃
=20°42′36〃