46 100 77 85
49 89 21 66
88
87
85
-3=1 5-=4 +4=7 6+=6
3-36-6 7+88+9 9+66+9
3.8+0.75= +0.625= ﹣= 2÷0.04= 0.45×80=
87﹣49= 450÷0.9= 34÷7= 6.25×40= 4.3×=