口算天地.+= ﹣= ×= ×=﹣×= ×= ×= ×=
合理、灵活地计算32×61.9+38.1×32 25×16×50×0.13 ×[0.75﹣(﹣)] (1﹣)÷[(0.1+1.1)÷0.2].
(1) (2)(3) (4).
计算(1)+9+999+9999 (2)4(2)(3)351 (4)(111+999).
4.85÷﹣3.6+6.15×3.
(1)16×(+0.125) (2)3×7+6.25÷(3)1111×37+9999×7 (4)36÷()