36°47′52〃×2
=72°94'104''
=72°95'44''
=73°35'44''
15°20′÷6
=(15×3600+20×60)/6秒
=15×600+20×10 秒
=9200'
=153'20''
=2°33'20''
36°47′52〃×2-15°20′÷6
=73°35'44''-2°33'20''
=71°2'24