度、分、秒的计算

①15°24′×5
=15°×5+24′×5
=75°+120′
=77°
②31°42′÷5（精确到1〃）
=(31°÷5)+42′÷5
=6°+(1°)÷5+42′÷5
=6°+102′÷5
=6°+20′+2′÷5
=6°+20′+120〃÷5
=6°20′24〃
③180°-79°19′
=179°60′-79°19′
=100°41′
④22°16′×5
=22°×5+16′×5
=110°+80′
=110°+2°+20′
=112°20′
⑤182°36′÷4
=182°÷4+36′÷4
=45°+2°÷4+36′÷4
=45°+156′÷4
=45°+39′
=45°39′
⑥126°13′-97°25′
=125°73′-97°25′
=28°48′
⑦23°37′×5
=23°×5+37′×5
=115°+185′
=115°+3×60′+5′
=115°+3°+5′
=118°5′
⑧21°17′×5+176°52′÷3
=21°×5+17′×5+176°÷3+52′÷3
=105°+85′+58°+2°÷3+52′÷3
=106°+25′+58°+172′÷3
=106°+25′+58°+57′+1′÷3
=164°+82′+60〃÷3
=164°+60′+22′+20〃
=165°22′20〃
⑨200°÷3-12°24′×5
=198°÷3+2°÷3-(12°×5+24′×5)
=66°+120′÷3-(60°+120′)
=66°+40′-62°
=4°+40′
=4°40′