1、口算: 40+30= 62-40= 25+30= 32-8= 86-50= 56-38= 35+25= 7+15= 90+50=
1、口算: 40+30= 62-40= 25+30= 32-8= 86-50= 56-38= 35+25= 7+15= 90+50=
70
22
55
24
36
18
60
140