5 7-5 14+4 14-4
3+8 8+3 17-2 14+3
1618﹣2 4+811
3+55+3 413﹣10
6+317﹣7 8+87+9
+-=
1-0.92= - = ×3.2= ÷ ×5=
3.5+4.28= × = ÷ = 99×0.9+0.9=