1. (2023一上·遂川期末) 口算

15-3=           9+8=          18-5=          4+7=          6-4=

6+9=          17-5=          5+8=          10-4=          7+6=

8-3=          4+8=          17-3=          5+7=            16-2=

16-2-4=       2+10+4=       8-2+4=       3+2+6=       9+9-2=