0.19+0.1= 20×70%= 1﹣= 2.7×4×2.5=
7.53﹣0.03= += +×0= 0.99÷0.1=
523﹣23×7
4.97+6.38+5.03﹣4.38
60×()
×3.2+5.6×0.5+1.2×50%
()÷
0×5.16= 9.8+2.6= 502-399=
÷4= × = 20×5=