-4.2+5.7-7.6+10.1-5.5
=5.7-4.2+10.1-7.6-5.5
=1.5+2.5-5.5
=4-5.5
=1.5
[-0.5]-[-3又4分之1】+【+275】 -｛+5又2分之1｝
=（-0.5)+3.25+2.75-5.5
=6-0.5-5.5
=0
-[-52]+[-19]-[+37]-[-24]
=52-19-37+24
=52+24-19-37
=76-19-37
=76-56
=20