(-0.5)+(3又1/4)+(+2.75)+(-5又1/20)
=-0.5+3.25+2.75-5.05
=6-5.55
=0.45
(+1又5/6)+(-2又1/2)+(+2/3)+(1/2)
=1+5/6-2-1/2+2/3+1/2
=5/6+4/6-1
=9/6-1
=3/2-1
=1/2
(-0.5)+(3又1/4)+(+2.75)+(-5又1/20)
=-0.5+3.25+2.75-5.05
=6-5.55
=0.45
(+1又5/6)+(-2又1/2)+(+2/3)+(1/2)
=1+5/6-2-1/2+2/3+1/2
=5/6+4/6-1
=9/6-1
=3/2-1
=1/2