0.42×0.308 0.76×0.32 4.32÷3.6 2.7+3.13
三、速算与巧算 (1)5.8+2.32+0.68+4.2
(2)1999+199.9+19.99+1.999
(3)12.59-3.24-5.76
(4)8.1+7.8+8.2+8.4+7.9+7.7
(5)18×5.5
(6)8.88×1.25
(7)34.7×0.25
(8)238÷1.25
(9)0.25×12.5×3.2
(10)124.68+324.68+524.68+724.68+924.68
(11)5795.5795÷5.7957×579.5
(12)1990×198.9-1989×198.8
(13)2.25×0.16+264×0.0225+5.2×2.25+0.225×20
(14)(1+0.28+0.84) ×(0.28+0.84+0.66)-(1+0.28+0.84+0.66)
(15)4.82×0.59+0.41×1.59-0.323×5.9
(0.28+0.84) ×
(16)0.125×0.25×32
(17)16×4.5
(18)0.25×1.25×22.4
(19)0.9+0.99+0.999+0.9999+0.99999
(20)(72×357+357×28)÷(51×7×4)