9+9= 15-6= 21-9= 9+17=
50-5= 37+30= 44+6= 68+5=
71-8= 90-9= 62-2= 20+63=
28-6= 45-7= 97-60= 32+40=
80-6= 75-9= 51+8= 66+5=
3+ =7 +8=10 7+ =13
| 78元 | 88元 | 98元 |
|
|
|
|

12-9=( )
50–30= 60–40= 40–40= 10+20=
50+50= 60–30= 40+50= 80–30=
100–20= 60+20= 40+30= 40–10=
50+10= 60–10= 40–20= 10+50=
50–50= 20+60= 70+20= 70–40=
30+20= 90–80= 20–20= 10+80=


- =
40+5050+30 80-4040+10 70-2070-50
20+6040+40 30+4040+30 60-5090-80


44+545+4 36+363+3 35+425+4
4842+7 91+8100 42+550