43°45′+47°40′37〃= 43°13′28〃除以2-10°5′18〃

题目

43°45′+47°40′37〃= 43°13′28〃除以2-10°5′18〃

答案

43°45′+47°40′37"
=(43°+45′)+(47°+40′+37")
=90°+85′+37"
=90°+60'+25′+37"
=91°+25′+37"
=91°25′37"
43°13′28"除以2-10°5′18"
=(43°+13′+28")/2-10°5′18"
=(42°+1°+12′+1'+28")/2-10°5′18"
=(42°+60'+12′+60"+28")/2-10°5′18"
=(42°+72'+88")/2-(10°+5′+18")
=42°/2+72'/2+88"/2-10°-5′-18"
=21°+36′+44"-10°-5′-18"
=11°+31′+26"
=11°31′26"