小数四则混合运算专项练习276题(有答案)ok

1、小数混合运算专项练习 276题（有答案）0.11 X 1.8+8.2 X 0.11(13 )1.25 X2.42.34 X 99+2.345.4 +2.7 X0.8132X 1016.25 + 1.25 +0.82.5 X 16.6.33 X 101 6.331.56 X 1.7+0.44 X 1.7(14 )5.85 + ( 1.3+0.5 ) X 6.(15 )17.17 6.8 3.2 6.17(16 )5.4 X (1.3+2.15 ) + 0.2(17 )8.4 + 0.6+8.4 +0.4(18 )16.8 X 10.1(19 )10.9 -0.9 +0.2+1.8(20 )1.2

2、5 X3.2 X 0.25 .(1)(2)(3)(4)(5)(6)(8)(9)(10 )(11)(12 )8.48 +0.8 X 0.9(24 )0.8 X ( 4 3.68 ) + 0.011.8 X (3.41 2.9) + 0.03(21)1.36+4.85+2.64+6.150.125 X 32X 2.5 .(22 )98.5 +2.5 +41.258 X 18.5 0.258 X 18.5(23 )5.4 + 2.5 X ( 3.7 2.9 )83.7 12.83 0.17(38 )25.46- 8.23 1.763.75X25+6.25X 25(50)125X 3.2X 2.55.

3、96+13 X (3.2 3.12 )(39 )2.9+7.1 X 104.32 +2.4 X 1.7 ;(40 )1.25 X 32 X 0.25.16.2 X4.5+3.8 X 4.5 ;(41)15.68- ( 7.78 4.32) - 2.329.05 3.86 3.14 ;(42 )0.25 X 3.2 X 1.257.28+0.72 + 0.9 .(43 )9.99X1.014.32+5.43+6.68(44 )4.63X1.4+46.3X0.8617.17-6.8- 3.2(45 )17.5 + 0.8+ 12.55.29X 9+5.29(46)0.9+9.9+99.9+999.

4、9 .16.8X 10.1(47)2.9X 99+2.92.74X 9.5+5 X 0.274(48)25X 11.2X40.36+9.6 + 3.2.(49)23.25- 6.75- 3.25.(25 )(26 )(27 )(28 )(29 )(30 )(31)(32 )(33 )(34 )(35 )(36 )(37 )3.6X 10.1(64 )0.125X 32X 2.5(51)(52 )(53 )(54 )(55 )(56 )(57 )(58 )(59 )(60 )(61)(62 )(63 )5.8X 2.7+0.58 X 73(65 )0.8X6.30.8X3.83.6+6.4X 1

5、.8(66 )504+ 3.2X 2.08(1.48+3.02) + ( 3.6X 0.5)(67 )(20 0.8X 9) X 5.7(36.7 4.9) X 101 31.8.(68 )2.4X 1.5+3.6+ 1.56.33X 101 6.33(69 )7.38-5.14+3.62 2.8635.6 5 X 1.73(70 )0.12X1.8+8.2X0.121.6X 55.4-55.4X 0.6(71)5.4+ 0.51 + (1.2 1.03 )17.68+5.2+2.7X 1.5.(72 ) (8.15.6) X 0.91.05+ 0.04.1.08 X 0.8 +0.27(73

6、)10.8-0.8- ( 0.35+0.05)102 X 0.45(74)8X 1 + ( 2.3-2.25)22.78 + 1.25 +0.8(75)2.64X9.9+0.2640.34 X 101 - 0.34 .(76)4.52+0.61+1.39+6.484.27 ( 1.96 - 1.73 )(90)9.6+0.4X0.25(77 )(78 )(79 )(80 )(81)(82 )(83 )(84 )(85 )(86 )(87 )(88 )(89 )(294.4 19.2 X 6) + ( 6+8)(91)29.7 + (5.85+0.65)12.5 X 0.76 X 0.4 X 8

7、X 2.5 .(92)7.4X 9.94.98+8.02X2.5(93)3.84-2.7X 0.6460.8 40.8+2.5(94)8.68 8.68+0.56X 0.50.8X 69.6 X 12.5(95)4.7X4.7+4.7+4.3X4.7.4.98X 99+4.9(96)2.72 + (8.2 6.5 ) X0.5;6.48+3.2 + 2.5(97)9.12+9.12 X 9-60.2 ;1.2X 7.6+7.6X6.8.(98)28.4 +0.4 +0.25 ;(9.4 5.8) X 2.07(99)27.36 27.36 +7.6 .12.54- 4.56- 3.44- 1.

8、54(100) 3.25 X 0.45+6.75 X 0.45(9.36X 5+9.36+9.36X2) X 1.25(101) 31.5 24.5+3.57.236+0.18 14.3X0.02.(102) 7.5X1026.3+3.7X 2.8.(116 ) 52.4 - ( 15+0.6) + 1.62.15+8.73+1.27+7.85(117) 9.87X99+9.8711.87 ( 8.2+1.87)(118 ) 46.8 + 0.9+0.45.42- 3.87- 1.13(119 )5.5X 17.3+6.7 X 5.5.(103 )(104 )(105 )(106 )(107

9、)(108 )(109 )(110)(111)(112 )(113 )(114 )(115 )4.38- 1.56+0.62 0.44(120) 99X4.2+4.20.4X 270X2.(121) 0.25X1.25X 3.2(40+1.25) X8(122 ) 6.4 X 14+15 X 6.4+6.4(12.50.05) X 8(123)(1.3+1.3X 0.125X 8) + ( 80 77.4)2.6X 8.5+8.5X 7.4(124) 4X ( 25+2.5+0.25) + 1119.9X 6.9- 6.9X 3.9(125)6.25+(17.2 3.6X4.5) +0.325

10、.6X 99+5.6(126) 28.4X99+28.42.5X ( 1.9+1.9+1.9+1.9)(127)0.94X2.5- 0.457.2+ 1.25 + 8.(128 )4X0.8X 12.5X 2.517.5-0.25X 17+13.(142 ) 2.4 X 1.5+3.6 +1.510.1X87(143) 0.32 X 0.25+0.08 +42.3+3.19+ (22 19.8)(144)(9.6+1.48 + 3.7) +81.25 X 7.2.(145 ) 5.8 + 4 X ( 1.34 - 0.14 )9.1 1.2+66.24(146 ) 5.4 + 0.51 + (

11、1.2 1.03).7.3+12.8 3.8X 2.3(147)21.35 3.25 16.75(5.36+7.64) + 13X 100(148)33.02 ( 148.4 90.85 ) + 2.5(129 )(130)(131)(132 )(133 )(134 )(135 )(136 )(137 )(138 )(139 )(140)(141)(149)32X2.5 X 0.1257.575+ (5.63 1.88) X 0.2.7.5 (5.5+1.24)(150)18.1+ (3 0.299 +0.23 ) X 1.0.26+15.68+9.74+2.32(151)67- (2.98+

12、0.67 )13.26+9.55 -3.26(152)8X 16 73.8 X66.1+3.9 6.1+3.9.(153)(45+14) + 73+710.31.7 +0.63 (保留2位小数)(154)13.7 X 0.125 X 80.8 X 13 - (3.12+5.28 )(168)18+ 0.3 X (8 6.5 )(155)(156)(157)(158)(159)(160)(161)(162)(163)(164)(165)(166)(167)102 X 0.56(169) 12.7+12.5+0.51.53 X 1.7+0.47 X 1.7 .(170) 91 + 2.6 +0.0

13、5=5.18+0.73+0.82(171)6.3 X 3.7+6.3 X6.3=0.75 X 1.8 + 1.5(172)(3.7+1.7 X 0.4 ) + 2.5=12.5 X 7.1 X 0.8(173)7.28+3.2 +2.5=6.12 X 99+6.12(174)0.74+0.9 X 7.4=8.6 + 0.86+8 X 0.35(175)7.8 + 0.125 + 0.8=5.6 X ( 18.5 8.5 +0.5 )(176)37.5 + 0.3 X ( 1.34 0.84)0.125 X4.78 X 80(177)(2.5+27.75 + 1.5 ) X 1.6 .2.8 X

14、 3.6+1.4 X2.8(178)6.21 -3.8+2.2(0.4+40) X 2.5(179)6.03+3.7+2.9778.7 17.7 X 3.6(180)17.43- 6.57- 2.4320.47 - ( 1.47+6.8)(193)7.75X 20+ ( 3.24 3.04).13.26+4.71+3.47+5.29(194)1.25X0.5X 8X 0.222.74+8.68 13.74.(195)0.97X9+0.9710+0.2 + 2.5(196)5.4-3 X ( 3.8- 2.9).64X4.5+3.6X45(197)0.4 X ( 3.2 0.8) + 0.151

15、.25 X 3.2 X 0.8(198)5.7+1.9 X 0.2 +7.614.5X 102(199)32.4 X 6.3+32.4 X 3.714.64+3.7 X2.8(200)18.2 - 10.6 X ( 0.9 0.75 )8.4+ 0.21+0.5.(201)0.25 X3.85 X 40(202)1.46 X3.5+3.5 X 4.54 .0.125X 9X8X 0.3(203)7X 12.5X 0.84.62+5+0.66(204)4.7 X 3.6+4.7X 6.45.78X2.3+5.78+5.78 X 6.7(205)1.45 X (2.8+4.4) +2.4.(181

16、)(182)(183)(184)(185)(186)(187)(188)(189)(190)(191)(192)(206)4.2X (6.18 3.03 )+6.3(219)0.6+0.94 0.2084.85X1.25X8(64 22.4+ 1.4) X 1.218.3-6.25-3.752.8X 3.6+1.4X 2.86.6+ 14.5- ( 1.7+1.8)0.25 X9.87 X 436.7 X 2.1 + 10.88.45 0.45 X 0.10.73 X 1027.8 X5.6+2.3 X4.476.3 X 27 76.3 X 17.7.05 X 23.7+7.05 X 76.3

17、 .(207) 15.02 -6.8 - ( 1.02+1.2 )(220)(208) 0.6X (5 0.68) +1.2(221)(209) 2.7+ 4+6.3 X 0.25(222)(210) (6.02+2.8 )+ 0.4 - 2.05(223)(211) 3.08 X 3.5+6.2 X 3.08+3.08X0.3 .(224)(212) 2.3+3.91 +(22 - 19.7)(225)(213) 21.6+ 64.8 - (48.6- 2.7X 2).(226)(214) 93.6 X 3.6+1.4 X 3.6(227)(215) 0.25 X 0.8 X 0.125 X

18、0.4(228)(216) 2.7 X 1.5 -2.7(229)(217) 9.08+5.45+11.92+4.55(230)(218) 1.25 X 30X 1.2 X 0.8.(231)(7.6 5.2) + 0.4+2.54 X32.(245)2.5 (6.84.9) X 0.8.17.68+5.2+2.7X 1.5(246)102X 4.5(232)(233)(234)(235)(236)(237)(238)(239)(240)(241)(242)(243)(244)35.6 5 X 1.73(247)3.4+ (1.2+0.5) X 5(248)8X ( 20- 1.25)(1.1

19、 0.78) X ( 2.7 1.95)1.3 X 0.75 X4(249)0.654+10.9X6.51.08 + 1.8 X 1.2(250)22.7X1.25X 0.850.4 X 1.9 - 1.8(251)3.91 X 2.8+6.09 X 2.8.0.82 X 0.25+1.18 X 0.25 .(252)6.23+3.09=8.5X (2.36+2.42) + 0.25(253)132.4- 59.8=3.9+ (1.3+0.6) X 6 - 3.6(254)6.62X0.84=4.25X6.3+3.7X4.25(255)2.07 + 0.023=205 X 0.99(256)2

20、0.026 ( 8.6+9.7 ) X 0.92 +30.19 .25.6- 7.49- 2.51(257)0.125X 32 X 2.5(258)0.8X 6.3- 0.8X 3.8(268)2.74 X 4.86+4.86 X 6.26+4.86(259)50.4+3.2X2.08(269) 0.08 X ( 12.5+2.5 ) X 0.1(260)204+ ( 3.4X 0.5)(270) 25.92+ (10.1 - 14.5 X 0.2 )(261)(43.26+2.34) + 7.5(271)0.487 X 12.5 +48.7(262)(20 0.8X 9) X 5.7.(26

21、3)13.25 - 0.8+1.75 - 1.2 ;(273)1.56X1.7+0.44X1.7(272)(8.16+2.09 ) + (10.39.3) +0.4.(264)2.5 X 99+2.5;(274) 12.5X (7.2 1.9) X 0.8(265) 10.36+4.8 16.5 +5;(275) 0.25 X 2010+20.10 X 75(266)12.5 X2.4.(276) 30.8+ (6.34 4.59) X 4.(267) 38.78 - 19.59+41.22 - 30.41参考答案(1) 0.11 X 1.8+8.2 X 0.11 ,=0.11 X ( 1.8

22、+8.2 ),=0.11 X 10, =1.1 ;(2) 2.34 X 99+2.34 ,=2.34 X ( 99+1),=2.34 X 100, =234;(3) 5.4 +2.7 X 0.8 ,=2X 0.8 , =1.6 ;(4) 132X101 ,=132X ( 100+1),=132X 100+132, =13332;(5) 6.25 + 1.25 +0.8 ,=6.25 + ( 1.25 X 0.8 ),=6.25 + 1 ,=6.25 ;(6) 2.5 X16, =(2.5 X4) X 4, =40 6.33X 101 - 6.33,=6.33X (101-1),=6.33 X

23、100, =633;(8) 1.56X 1.7+0.44X 1.7,=1.7X ( 1.56+0.44),=1.7X 2, =3.4;(9) 1.8 X (3.41 2.9) + 0.03,=1.8 X 0.51 +0.03,=1.8X 17, =30.6;(10) 0.125X 32X 2.5,=(0.125X8) X ( 4X 2.5),=1 X 10, =10(11) 1.258 X 18.5 - 0.258 X 18.5 ,=18.5 X ( 1.258 - 0.258),=18.5 X 1 ,=18.5 ;(12) 8.48 +0.8 X0.9 ,=10.6 X 0.9 ,=9.54

24、 ;(13) 1.25 X2.4 ,=1.25 X 8X 0.3 ,=10X 0.3 ,=3；(14) 5.85 + ( 1.3+0.5 ) X 6,=5.85 + 1.8 X6,=3.25 X6,=19.5(15) 17.17 - 6.8 - 3.2 - 6.17=(17.17 -6.17) - ( 6.8+3.2 ),=1110,=1；(16) 5.4 X (1.3+2.15 ) + 0.2=5.4 X 3.45 + 0.2,=5.4 X 17.25 ,=93.15 ;(17) 8.4+0.6+8.4 +0.4=14+21=35;(18) 16.8 X 10.1=16.8 X 10+16.

25、8 X 0.1 ,=168+1.68 ,=169.68 ;(19) 10.9 - 0.9 +0.2+1.8=10.9 - 4.5+1.8 ,=8.2 ;(20) 1.25 X 3.2 X 0.25=(1.25 X 0.8 ) X ( 4 X 0.25 ),=1X1,=1(21) 1.36+4.85+2.64+6.15 ,=(1.36+2.64 ) + (4.85+6.15 ),=4+11,=15;(22) 98.5 +2.5 +4,=98.5 + ( 2.5 X4),=98.5 + 10,=9.85 ;(23) 5.4 + 2.5 X ( 3.7 - 2.9 ),=5.4 + 2.5 X 0.

26、8,=5.4 +2,=2.7 ;(24) 0.8 X ( 4- 3.68 ) + 0.01 ,=0.8 X 0.32 +0.01 ,=0.256 +0.01 ,=25.6 ;(25) 83.7 - 12.83 - 0.17 ,=83.7 - ( 12.83+0.17 ),=83.7 - 13,=70.7 ;(26) 5.96+13 X ( 3.2 - 3.12 ), =5.96+13 X0.08 , =5.96+1.04 , =7.(27) 4.32 +2.4 X 1.7 ,=1.8 X 1.7 , =3.06 ;(28) 16.2 X4.5+3.8 X 4.5 ,=(16.2+3.8 ) X

27、 4.5 ,=20X4.5 ,=90;(29) 9.05 - 3.86 -3.14 ,=9.05 - ( 3.86+3.14 ),=9.05 - 7,=2.05 ;(30) 7.28+0.72 +0.9, =7.28+0.8 ,=8.08(31) 4.32+5.43+6.68 , =4.32+6.68+5.43 , =11+5.43 , =16.43 ;(32) 17.17 - 6.8 -3.2 ,=17.17 - (6.8+3.2 ),=17.17 - 10,=7.17 ;(33) 5.29 X 9+5.29,=5.29 X ( 9+1),=5.29 X 10,=52.9 ;(34) 16.

28、8 X 10.1 ,=16.8 X 10+16.8 X 0.1 , =168+1.68 , =169.68 ;(35) 2.74 X 9.5+5 X 0.274 , =2.74 X 9.5+0.5 X 2.74 , =2.74 X ( 9.5+0.5 ), =2.74 X 10, =27.4 ;(36) 0.36+9.6 + 3.2,=0.36+3 , =3.36(37) 3.75 X 25+6.25 X 25,=25 X ( 3.75+6.25 ),=25X10,=250;(38) 25.46 - 8.23 - 1.76 ,=25.46 - ( 8.23+1.76 ),=25.46 - 9.

29、99=15.45 ;(39) 2.9+7.1 X 10,=2.9+71 ,=73.9 ;(40) 1.25 X 32X 0.25=(1.25 X 8) X ( 4X 0.25 ),=10X 1,=1.(41) 15.68 - ( 7.78 - 4.32 ) - 2.32 ,=15.68 - 7.78+4.32 - 2.32 ,=(15.68+4.32 ) - ( 7.78+2.32 ),=20-10,=10;(42) 0.25 X 3.2 X 1.25 ,=0.25 X 4X 0.8 X 1.25 ,=(0.25 X 4) X ( 0.8 X 1.25 ),= 1X1,=1;(43) 9.99

30、 X 1.01 ,=(10- 0.01 ) x 1.01 ,=10.1 - 0.0101 ,=10.0899 ;(44) 4.63 X 1.4+46.3 X 0.86 ,=46.3 X 0.14+46.3 X 0.86 ,=46.3 X ( 0.14+0.86 ),=46.3 X 1 ,=46.3 ;(45) 17.5 +0.8 + 12.5 ,=17.5 + ( 0.8 X 12.5 ),=17.5 + 1 ,=17.5 ;(46) 0.9+9.9+99.9+999.9 ,=1 - 0.1 + 10 - 0.1 + 100 - 0.1 + 1000 - 0.1 ,=(1+10+100+100

31、0) - ( 0.1+0.1+0.1+0.1 ),=1111-0.4 ,=1110.6(47) 2.9 X 99+2.9=(99+1) X 2.9 ,=100X 2.9 ,=290;(48) 25X 11.2 X4=25X4X 11.2 ,=100 X 11.2 ,=1120;(49) 23.25 - 6.75 - 3.25=23.25 - ( 6.75+3.25 ),=23.25 - 10,=13.25(50) 125X 3.2 X 2.5 ,=125X 8X 0.4 X 2.5 ,=(125X8) X ( 0.4 X2.5 ),=1000X 1,=1000;(51) 3.6 X 10.1

32、,=3.6 X (10+0.1 ),=3.6 X 10+3.6 X 0.1 ,=36+0.36 ,=36.36 ;(52) 5.8 X 2.7+0.58 X 73,=5.8 X 2.7+5.8 X 7.3 ,=5.8 X ( 2.7+7.3 ),=5.8 X 10,=58;(53) 3.6+6.4 X1.8,=3.6+11.52 ,=15.12 ;(54) (1.48+3.02 ) + ( 3.6 X 0.5 ),=4.5 + 1.8 ,=2.5 ;(55) (36.7 - 4.9 ) X 101 -31.8 ,=31.8 X 101 - 31.8 ,=31.8 X ( 101- 1),=31

33、.8 X 100,=3180(56) 6.33 X 101 - 6.33=6.33 X ( 101- 1),=6.33 X 100,=633;(57) 35.6 - 5X 1.73 ,=35.6 - 8.65 ,=26.95 ;(58) 1.6 X 55.4 - 55.4 X 0.6 ,=55.4 X ( 1.6 - 0.6 ),=55.4 X 1 ,=55.4 ;(59) 17.68 +5.2+2.7 X 1.5 ,=3.4+4.05 ,=7.45(60) 1.08 X 0.8 +0.27=1.08 +0.27 X 0.8 ,=4X 0.8 ,=3.2 ;(61) 102X0.45=(100

34、+2) X 0.45 ,=100 X 0.45+2 X0.45 ,=45+0.9 ,=45.9 ;(62) 22.78 + 1.25 +0.8=22.78 + ( 1.25 X 0.8 ),=22.78 + 1,=22.78 ;(63) 0.34 X 101 - 0.34=(101 - 1) X 0.34 ,=100 X 0.34 ,=34(64) 0.125 X 32X2.5 ,=(0.125 X 8) X ( 4X 2.5),=1X 10,= 10;(65) 0.8 X6.3 - 0.8 X 3.8 ,=0.8 X ( 6.3 - 3.8),=0.8 X2.5 ,=2；(66) 504+3

35、.2 X 2.08 ,=157.5 X 2.08 ,=327.6 ;(67) (20- 0.8 X 9) X 5.7 ,=(20- 7.2 ) X 5.7 ,=12.8 X 5.7 ,=72.96(68) 2.4 X 1.5+3.6 + 1.5 ,=3.6+2.4 ,=6；(69) 7.38 - 5.14+3.62 - 2.86 , =(7.38+3.62 ) - ( 5.14+2.86 ), =11 8, =3；(70) 0.12 X 1.8+8.2 X 0.12 ,=0.12 X ( 1.8+8.2 ),=0.12 X 10,=1.2 ;(71) 5.4 + 0.51 + ( 1.2 1.

36、03 ),=5.4 + 0.51 + 0.17,=5.4 +3,=1.8 ;(72) (8.1 5.6) X 0.9 - 1.05 +0.04, =2.5 X 0.9 - 1.05 +0.04 , =2.25 - 1.05 +0.04 , =1.2 +0.04 , =30(73) 10.8 - 0.8 - ( 0.35+0.05 ),=10.8 - 0.8 +0.4 ,=10.8 -2,=8.8 ;(74) 8X 1 + ( 2.3 - 2.25 ),=8X 1 +0.05,=8X20, =160;(75) 2.64 X 9.9+0.264 ,=0.264 X 99+0.264 ,=0.264

37、 X (99+1),=0.264 X 100,=26.4 ;(76) 4.52+0.61+1.39+6.48 =(4.52+6.48 ) + (0.61 + 1.39 ), =11+2, =13；(77) 4.27 - ( 1.96 - 1.73 )=4.27 - 0.23 ,=4.04 ;(78) (294.4 - 19.2 X6) + ( 6+8) =(294.4 - 115.2 ) + 14, =179.2 + 14, =12.8 ;(79) 12.5 X 0.76 X0.4 X 8X2.5=(12.5 X 8) X ( 0.4 X 2.5 ) X 0.76 , =100 X 1 X 0

38、.76 , =76.(80) 4.98+8.02 X2.5, =4.98+20.25 , =25.03 ;(81) 60.8 - 40.8 +2.5 ,=60.8 - 16.32 ,=44.48 ;(82) 0.8 X 69.6 X 12.5 ,=(0.8 X 12.5) X 69.6 ,=10X69.6 ,=696;(83) 4.98 X 99+4.9 , =493.02+4.9 , =497.92 ;(84) 6.48 +3.2 +2.5 ,=6.48 + ( 3.2 X 2.5 ),=6.48 +8,=0.81 ;(85) 1.2 X 7.6+7.6 X 6.8 ,=7.6 X ( 1.

39、2+6.8 ),=7.6 X 8,=60.8(86) (9.4-5.8) >2.07,=3.6X2.07,=7.452;(87) 12.54- 4.56- 3.44- 1.54,=(12.54 1.54) ( 4.56+3.44),=11 8,=3；(88) (9.36X5+9.36+9.36 0 M.25,=9.36 X (5+2+1 ) X1.25,=9.36%M.25,=9.36 X (8M.25),=93.6;(89) 7.236田.18T4.3>0.02,=40.2 - 0.286, =39.914.(90) 9.6 +0.4 X 0.25 ,=24 X 0.25 ,=6

40、；(91) 29.7 + (5.85 + 0.65 ),=29.7 +9,=3.3 ;(92) 7.4 X 9.9 ,=7.4 X (10-0.1 ),=7.4 X 10- 7.4 X 0.1 ,=74 - 0.74 ,=73.26 ;(93) 3.84 - 2.7 X 0.64 ,=3.84 - 1.728 ,=2.112 ;(94) 8.68 8.68 +0.56 X 0.5 ,=8.68 - 15.5 X 0.5 ,=8.68 - 7.75 ,=0.93 ;(95) 4.7 X4.7+4.7+4.3 X 4.7 , =4.7 X ( 4.7+4.3+1 ), =4.7 X 10, =47

41、(96) 2.72 + (8.2 6.5) X 0.5=2.72 + 1.7 X 0.5,=2.72 + 0.85 ,=3.2 ;(97) 9.12+9.12 X 9- 60.2=(1+9) X 9.12 - 60.2 ,=10X 9.12 - 60.2 ,=91.2 - 60.2 ,=31;(98) 28.4 +0.4 +0.25=28.4 + ( 0.4 X0.25 ),=28.4 +0.1 ,=284;(99) 27.36 - 27.36 +7.6=27.6 - 3.6 ,=24(100) 3.25 X 0.45+6.75 X 0.45 , =0.45 X ( 3.25+6.75 ),

42、=0.45 X 10, =4.5 ;(101) 31.5 24.5 +3.5 ,=31.5 - 7,=24.5 ;(102) 7.5 X 102, =7.5 X (100+2), =7.5 X 100+7.5 X 2, =750+15, =765;(103) 6.3+3.7 X2.8, =6.3+10.36 , =16.66 .(104) 2.15+8.73+1.27+7.85 =(2.15+7.85 ) + (8.73+1.27 ), =10+10, =20;(105) 11.87 ( 8.2+1.87 ), =11.87 - 1.87 - 8.2 , =10 - 8.2 , =1.8 ;(

43、106) 5.42 - 3.87 - 1.13 ,=5.42 - 5, =0.42 ;(107) 4.38 - 1.56+0.62 - 0.44 , =(4.38+0.62 ) - ( 1.56+0.44 ), =5-2, =3；(108) 0.4 X 270X2.5 , =(0.4 X 2.5 ) X 270, =270;(109) (40+1.25 ) X 8,=40X 8+1.25 X 8, =320+10, =330;(110) (12.5 0.05 ) X 8,=12.5 X 8-0.05 X 8,=100-0.4 ,=99.6 ;(111) 2.6 X 8.5+8.5 X 7.4

44、,=(2.6+7.4 ) X 8.5 , =85;(112) 9.9 X6.9 - 6.9 X 3.9 ,=(9.9 - 3.9 ) X 6.9 ,=6X6.9 ,=41.4 ;(113) 5.6 X 99+5.6 ,=5.6 X ( 99+1), =560;(114) 2.5 X ( 1.9+1.9+1.9+1.9 ),=2.5 X4X 1.9 ,=10X 1.9 , =19;(115) 7.2 +1.25 +8,=7.2 +8+1.25 ,=0.9 - 1.25 ,=0.72 .(116) 52.4 - ( 15+0.6) + 1.6 ,=52.4 - 15.6 - 1.6 ,=52.4

45、- 9.75 ,=42.65 ;(117) 9.87 X 99+9.87 ,=9.87 X ( 99+1),=987;(118) 46.8 + 0.9 + 0.4 ,=46.8 + ( 0.9 X0.4 ),=46.8 + 0.36 , =130;(119) 5.5 X 17.3+6.7 X 5.5 ,=5.5 X ( 17.3+6.7 ),=5.5 X 24,=132(120) 99X4.2+4.2=4.2 X ( 99+1),=4.2 X 100, =420;(121) 0.25 X 1.25 X 3.2=0.25 X 1.25 X ( 4X 0.8 ),=0.25 X4X ( 1.25

46、X 0.8 ),=1X1,=1；(122) 6.4 X 14+15X 6.4+6.4=6.4 X (14+15+1),=6.4 X 30, =192;(123) (1.3+1.3 X 0.125 X 8) + ( 80- 77.4 )=(1.3+1.3 X 1) + 2.6 ,=2.6 +2.6 , =1；(124) 4X (25+2.5+0.25 )+ 111=(4 X 25+4X 2.5+4 X 0.25 ) + 111,=(100+10+1) + 111,=111 + 111,二1；(125) 6.25 - (17.23.6X4.5) +0.32=6.25 + (17.2 - 16.2

47、) + 0.32,=6.25 + ( 1+0.32 ),=6.25 +3.125 ,=2(126) 28.4 X 99+28.4 ,=28.4 X ( 99+1),=28.4 X 100,=2840.(127) 0.94 X 2.5 -0.45 ,=2.35 - 0.45 ,=1.9 .(128) 4X 0.8 X 12.5 X2.5 ,=(4X2.5) X ( 0.8 X12.5),=10X 10,=100.(129) 17.5 +0.25 X 17+13,=70X17+13,=1190+13,=1203(130) 10.1 X 87,=(10+0.1 ) X 87,=87+8.7 ,=95

48、.7 ;(131) 2.3+3.19 - (22- 19.8),=2.3+3.19 +2.2 ,=2.3+1.45 ,=3.75 ;(132) 1.25 X 7.2 ,=1.25 X 8X0.9 ,=10X0.9 ,=9(133) 9.1 - 1.2 +6-6.24=9.1 - 0.2 - 6.24 ,=8.9 - 6.24 ,=2.66 ;(134) 7.3+12.8 3.8 X 2.3=20.1 - 8.74 ,=11.36 ;(135) (5.36+7.64 ) + 13X 100=13+ 13X 100,=100;(136) 7.575 - (5.63 1.88 ) X 0.2=7.5

49、75 + 3.75 X 0.2,=7.575 + 0.75 ,=10.1(137) 7.5 (5.5+1.24 ),=7.5 - 5.5 -1.24,=2 -1.24,=0.76 ;(138) 0.26+15.68+9.74+2.32,=(0.26+9.74 ) + (15.68+2.32 ),=10+18,=28;(139) 13.26+9.55 - 3.26 ,=13.26 - 3.26+9.55 ,=10+9.55 ,=19.55 ;(140) 6.1+3.9 - 6.1+3.9 ,=6.1 - 6.1+ (3.9+3.9 ),=0+7.8 ,=7.8(141) 31.7 + 0.63 50.32 ;(142) 2.4 X 1.5+3.6 +1.5=3.6+2.4 ,=6；(143) 0.32 X 0.25+0.08