78度-47度34分45秒 12度34分*5 25.5度除4

78°-47°34′45′
=77°59′60″-47°34′45′
=(77°-47°)+(59′-34′)+(60″-45″)
=30°+25′+15″
=30°25′15″
12°34′×5
=(12°+34′)×5
=12°×5+34′×5
=60°+170′
=60°+120′+50′
=60°+2°+50′
=62°50′
25.5°÷4
=6.375°
=6°+0.375°
=6°+(0.375×60)′
=6°+22.5′
=6°+22′+0.5′
=6°+22′+(0.5×60)″
=6°+22′+30″
=6°22′30″