=(1+9)×0.74, =10×0.74, =7.4;
(175)7.8÷0.125÷0.8, =7.8÷(0.125×0.8), =7.8÷0.1, =78
(176)37.5÷[0.3×(1.34﹣0.84)], =37.5÷[0.3×0.5], =37.5÷0.15, =250; (177)(2.5+27.75÷1.5)×1.6, =1×3.2, =3.2;
(187)14.5×102, =14.5×(100+2), =14.5×100+14.5×2, =1450+29, =1479;
(188)14.64+3.7×2.8, =14.64+10.36, =25;
(189)8.4÷0.21÷0.5, =40÷0.5, =(2.5+18.5)×1.6, =21×1.6, =33.6
(178)6.21﹣3.8+2.2, =2.41+2.2, =4.61;
(179)6.03+3.7+2.97, =(6.03+2.97)+3.7, =9+3.7, =12.7;
(180)17.43﹣6.57﹣2.43, =17.43﹣(6.57+2.43), =17.43﹣9, =8.43;
(181)20.47﹣(1.47+6.8), =20.47﹣1.47﹣6.8, =19﹣6.8, =12.2;
(182)13.26+4.71+3.47+5.29, =(13.26+3.47)+(4.71+5.29), =16.73+10, =26.73;
(183)22.74+8.68﹣13.74, =(22.74﹣13.74)+8.68, =9+8.68, =17.68
(184)10÷0.2÷2.5, =10÷(0.2×2.5), =10÷0.5, =20;
(185)64×4.5+3.6×45, =6.4×45+3.6×45, =(6.4+3.6)×45, =10×45, =450;
(186)1.25×3.2×0.8, =(1.25×0.8)×3.2,
小数混合运算---
=80
(190)0.125×9×8×0.3, =(0.125×8)×(9×8), =1×72, =72;
(191)4.62÷5÷0.66, =4.62÷(5×0.66), =4.62÷3.3, =1.4;
(192)5.78×2.3+5.78+5.78×6.7, =5.78×(2.3+1+6.7), =5.78×10, =57.8;
(193)7.75×[20÷(3.24﹣3.04)],=7.75×[20÷0.2], =7.75×100, =775
(194)1.25×0.5×8×0.2, =(1.25×8)×(0.5×0.2), =10×0.1, =1;
(195)0.97×9+0.97, =0.97×(9+1), =0.97×10, =9.7;
(196)5.4÷[3×﹙3.8﹣2.9﹚], =5.4÷[3×0.9], =5.4÷2.7, =2
(197)0.4×(3.2﹣0.8)÷0.15, =0.4×2.4÷0.15, =0.96÷0.15, =6.4;
(198)5.7+1.9×0.2÷7.6, =5.7+0.38÷7.6, =5.7+0.05, =5.75;
26
(199)32.4×6.3+32.4×3.7, =32.4×(6.3+3.7), =32.4×10, =324;
(200)18.2﹣10.6×(0.9﹣0.75), =20;
(211)3.08×3.5+6.2×3.08+3.08×0.3, =(3.5+6.2+0.3)×3.08, =10×3.08, =30.8
=18.2﹣10.6×0.15, =18.2﹣1.59, =16.61;
(201)0.25×3.85×40, =0.25×40×3.85, =10×3.85, =38.5;
(202)1.46×3.5+3.5×4.54, =3.5×(1.46+4.54), =3.5×6, =21
(203)7×12.5×0.8, =7×(12.5×0.8), =7×10, =70;
(204)4.7×3.6+4.7×6.4, =4.7×(3.6+6.4), =4.7×10, =47;
(205)1.45×[(2.8+4.4)÷2.4],=1.45×[7.2÷2.4], =1.45×3, =4.35
(206)4.2×(6.18﹣3.03)+6.3,=4.2×3.15+6.3, =13.23+6.3, =19.53;
(207)15.02﹣6.8﹣(1.02+1.2 ),=15.02﹣6.8﹣1.02﹣1.2, =(15.02﹣1.02)﹣(6.8+1.2), =14﹣8, =6;
(208)0.6×[(5﹣0.68)÷1.2],=0.6×[4.32÷1.2], =0.6×3.6, =2.16;
(209)2.7÷4+6.3×0.25, =2.7×0.25+6.3×0.25, =(2.7+6.3)×0.25, =9×0.25, =2.25; (210)(6.02+2.8 )÷0.4﹣2.05,=8.82÷0.4﹣2.05, =22.05﹣2.05,
小数混合运算---
(212)2.3+3.91÷(22﹣19.7), =2.3+3.91÷2.3, =2.3+1.7, =4;
(213)21.6÷[64.8﹣(48.6﹣2.7×2)], =21.6÷[64.8﹣(48.6﹣5.4)], =21.6÷[64.8﹣43.2], =21.6÷21.6, =1
(214)93.6×3.6+1.4×3.6, =(93.6+1.4)×3.6, =95×3.6,
=(100﹣5)×3.6, =100×3.6﹣5×3.6, =360﹣18, =342;
(215)0.25×0.8×0.125×0.4, =(0.25×0.4)×(0.8×0.125), =0.1×0.1, =0.01;
(216)2.7×1.5﹣2.7, =2.7×(1.5﹣1), =2.7×0.5, =1.35;
(217)9.08+5.45+11.92+4.55, =(9.08+11.92)+(5.45+4.55), =21+10, =31;
(218)1.25×30×1.2×0.8, =(1.25×0.8)×(30×1.2), =1×36, =36
(219)0.6+0.94﹣0.208, =1.54﹣0.208, =1.332;
(220)4.85×1.25×8, =4.85×(1.25×8), =4.85×10, =48.5; (221)(64﹣22.4÷1.4)×1.2, =(64﹣16)×1.2, =48×1.2, =57.6;
27
(222)18.3﹣6.25﹣3.75, =18.3﹣(6.25+3.75), =18.3﹣10, =8.3;
(223)2.8×3.6+1.4×2.8, =2.8×(3.6+1.4), =2.8×5, =14;
(224)6.6÷[14.5﹣(1.7+1.8)], =6.6÷[14.5﹣3.5], =6.6÷11, =0.6
(225)0.25×9.87×4, =0.25×4×9.87, =1×9.87, =9.87;
(226)7×2.1+10.8, =77.07+10.8, =87.87;
(227)8.45﹣0.45×0.1, =8.45﹣0.045, =8.405;
(228)0.73×102, =0.73×(100+2), =0.73×100+0.73×2, =73+1.46, =74.46;
(229)7.8×5.6+2.3×4.4, =43.68+10.12, =53.8;
(230)76.3×27﹣76.3×17 =76.3×(27﹣17), =76.3×10, =763.
(231)7.05×23.7+7.05×76.3 =(23.7+76.3)×7.05, =100×7.05, =705
(232)[(7.6﹣5.2)÷0.4+2.54]×32, =[2.4÷0.4+2.54]×32, =[6+2.54]×32, =8.54×32, =273.28
(233)17.68÷5.2+2.7×1.5, =3.4+4.05, =7.45;
(234)35.6﹣5×1.73, =35.6﹣8.65, =26.95;
小数混合运算---
(235)(1.1﹣0.78)×(2.7﹣1.95), =0.32×0.75, =0.24
(236)1.3×0.75×4, =1.3×3×0.25×4, =1.3×3×(0.25×4), =3.9×1, =3.9;
(237)1.08÷1.8×1.2, =0.6×1.2, =0.72;
(238)50.4×1.9﹣1.8, =95.76﹣1.8, =93.96;
(239)0.82×0.25+1.18×0.25, =(0.82+1.18)×0.25, =2×0.25, =0.5
(240)8.5×[(2.36+2.42)÷0.25], =8.5×[4.78÷0.25], =8.5×19.12, =162.52;
(241)3.9÷[(1.3+0.6)×6﹣3.6], =3.9÷[1.3×0.6+0.6×6﹣3.6], =3.9÷[0.78+3.6﹣3.6], =3.9÷0.78, =5;
(242)4.25×6.3+3.7×4.25, =4.25×(6.3+3.7), =4.25×10, =42.5;
(243)205×0.99, =205×(1﹣0.01), =205×1﹣205×0.01, =205﹣2.05, =202.95;
(244)25.6﹣7.49﹣2.51, =25.6﹣(7.49+2.51), =25.6﹣10, =15.6;
(245)[2.5﹣(6.8﹣4.9)]×0.8, =[2.5﹣1.9]×0.8, =0.6×0.8, =0.48
(246)102×4.5, =(100+2)×4.5, =100×4.5+2×4.5, =450+9,
28
=459;
(247)3.4÷[(1.2+0.5)×5], =3.4÷[1.7×5], =3.4÷8.5, =0.4;
(248)8×(20﹣1.25), =8×20﹣8×1.25, =160﹣10, =150;
(249)0.654+10.9×6.5, =0.654+70.85, =71.504;
(250)22.7×1.25×0.8, =22.7×(1.25×0.8), =22.7×1, =22.7;
(251)3.91×2.8+6.09×2.8, =(3.91+6.09)×2.8, =10×2.8, =28
(252)6.23+3.09=9.32, 6.23
;
(253)132.4﹣59.8=72.6; 132.4
;
(254)6.62×0.84=5.5608; 6.62
;
(255)2.07÷0.023=90;
(256)[20.026﹣(8.6+9.7)×0.92]÷30.19, =[20.026﹣18.3×0.92]÷30.19, =[20.026﹣16.836]÷30.19, =3.19÷30.19, =.
小数混合运算---
(257)0.125×32×2.5, =0.125×8×4×2.5,
=(0.125×8)×(4×2.5), =1×10, =10;
(258)0.8×6.3﹣0.8×3.8, =(6.3﹣3.8)×0.8, =2.5×0.8, =2;
(259)50.4÷3.2×2.08, =15.75×2.08, =32.76;
(260)204÷(3.4×0.5), =204÷1.7, =120; (261)(43.26+2.34)÷7.5, =45.6÷7.5, =6.08; (262)(20﹣0.8×9)×5.7, =(20﹣7.2)×5.7, =12.8×5.7, =72.96
(263)13.25﹣0.8+1.75﹣1.2, =(13.25+1.75)﹣(1.2+0.8), =15﹣2, =13;
(264)2.5×99+2.5, =2.5×(99+1), =2.5×100, =250;
(265)10.36+4.8﹣16.5÷5, =10.36+4.8﹣3.3, =15.16﹣3.3, =11.86;
(266)12.5×2.4, =12.5×(8×0.3), =(12.5×8)×0.3, =100×0.3, =30
(267)38.78﹣19.59+41.22﹣30.41,=38.78+41.22﹣19.59﹣30.41,
=(38.78+41.22)﹣(19.59+30.41),=80﹣50, =30;
(268)2.74×4.86+4.86×6.26+4.86,=(2.74+6.26+1)×4.86, =10×4.86, =48.6;
(269)0.08×(12.5+2.5)×0.1,
29
=(0.08×12.5+0.08×2.5)×0.1, =(1+0.2)×0.1, =1.2×0.1, =0.12;
(270)25.92+(10.1﹣14.5×0.2), =25.92+(10.1﹣2.9), =25.92+7.2, =33.12;
(271)0.487×12.5÷48.7, =0.487÷48.7×12.5, =0.01×12.5, =0.125; (272)(8.16+2.09)÷[(10.3﹣9.3)÷0.4], =10.25÷[1÷0.4], =10.25÷2.5, =4.1
(273)1.56×1.7+0.44×1.7, =(1.56+0.44)×1.7, =2×1.7,
小数混合运算--- =3.4;
(274)12.5×(7.2﹣1.9)×0.8, =12.5×5.3×0.8, =12.5×0.8×5.3, =10×5.3, =53;
(275)0.25×2010+20.10×75, =0.25×2010+2010×0.75, =2010×(0.25+0.75), =2010×1, =2010;
(276)30.8÷[(6.34﹣4.59)×4], =30.8÷[1.75×4], =30.8÷7, =4.4.
30
小数混合运算--- 31