计算

80-60=         50 +20=        85-80=      73 +20=

83-9=            47+8=          56-34 =       23+55=

3×7=             49÷7=        4×8=         32÷4=

5×9=              18÷9=         6×4 =        12÷2=

8×7+8=            3×7+26=       6×7-25 =     48÷8+45=