小學(xué)總復(fù)習(xí)簡便運算238題(有答案)

1、小學(xué)數(shù)學(xué)簡便運算專項練習(xí)238題（有答案）1. (0. 86+0. 86+0. 86+0. 86) X259. 21x232410. 3是-15.38+61. 25 - 3. 623. 1254- (50+8)11. 17. 98+2.5X0.3- 18-M. 544. 7.6xi1.9- 1.9X (1.9- 1.9).212-5. 999X999 - 2X999+1.13.6. 1.25X0. 25X0. 05X644. 76+5和5. 2414.87. 20. 06 X 65+380 X 2. 006 - 2. 006 X 30.115.斗 一（0.16+1） -1.8423. 56X

2、（至-苣+工）7 8 2816.2.8- （0.43+日十1段）J J24. 0. 279X258+0. 742X2792 / 302 / 302 / 3015數(shù)學(xué)簡便運算17. 9.56-3一525. 1328+11-27+154-28+384-27.18. 22.7X1.25X0.826.X24X1519. 3.91X2.8+6.09X2.8.27. 3.7X+5.3X0.75+W4420. 23.4X16 - 23.4X628. 9. 9+99. 9+999. 921. 2定-5. 75 - 14. 25629. 6.84-4- 1.2X25%+4X0. 25.522. 1.25X0.

3、25X3230. 6. 3+6. 44+2. 7+3. 5631. 15. 35 - (5. 35+7.2)39. 3.64-4+4.36X0.2532. 600 + 1233. 67X102.4. 85-+5.15-434. 9935. ix (痛一 三一 3.6+6.15義3±)94 18536尹中*|3Z電咕+喘+臉+%38. 1.3 - 3.79+9.7 -6.21，米 (至X (2-1)40, 96 28 241.匪 X4. 25+4iX-i64 642. (1-J-)X4X99 1243. 1+2+3+4+-+49+50.44.4.8X0.2545. 233X0.5X44

4、6. 1.2X2.5+0.8X2.554. 47X10147. 3.74-1.258.55, 573 - 29848. 43.6+9.8+6.456. 194+50149. 173X0.25X857. 627 - (427+189)50. 2.31X1.5+1.5X7.69.58. 630+1451. 10.24 - 6.67- 13359. 125X25X3252. 32000+125 + 860.210+6+5.53. 7.31 + 15.05+2.69+4.9561. 125X3262. 6404-54-870. 5X25X13X40X20.63. 653 - 9871. 73504-2

5、564. 944+102.72. 54X10165. 25X79X473. 227+364+146+17366. 8X166X2574. 5604 - (723+1604)67. 50X25X4X35Xl.67+0. 33X至75. 8868. 8X (25X15)76. 999X667+667.69. (250X72) X477. 2。4乂器78. 81 - (3.81 - 1.65) +2.2586. 45X98+45X279. 24 X (至-L2).6 4 387, 452 - (152+240)80. (2+工)X243 488. 99X2789. 1120-4-16782. 2.5

6、X3.2X1.2590. 113X36 - 13X3683. 4. 05 - (2. 05tA)2791. 179 - 245+321 - 155.92. 1. 24+14. 95+8. 76 - 4. 9584. 5. 39+帝.6噂93. 52. 7 - 5. 27 - 2. 785. 0. 588 X i2+4X9. 412+/X0. 588. 3394. 35X201102. 1927 - 528 - 472.95. 4500 + 25 + 4103. (1+1-L) X1053 5 1596. 125X32104. x1t25%X-?+o. 25X-17 47797. 654 XX

7、99+346X99.105.98. 56X12.5106. 3. 7X99-3. 7107. I.2X2.5+2.8X2.599. 14.6- (4.6+7.2)108. 4.8 X 2.5.100. 99X99+199.101. 0. 125X0. 25X8X4109. 4. 05 - 2. 86 - 0. 14110. 7苣X 苣+0.4X724 54118. liXtl34-?111. 2. 25X3. 14X4+3. 14119.工一1TT 5TT112.(工-工)X17X15.15 51120. -ixi2.5X8X0.44113. 6.3X8.7+8.7X3.7121. 24XX1

8、2.8 6114. (1-U) X123 6 4122. 25X0.32X 1.25115.115-123. 0.37X79+3.7X2.1116. 7.25 - 3+3.75 -6124. 2011 + 201 但旦+一2012 2013117. 49 X (2+1) X257 5125. l/+工+工26 20 30126.12 2X12133. (40+8) X25127.1000+999X999.134. 73X99135. 54X11 - 54.128.178.4-45.3 - 54.7136. 301X79129.456 - (256 -144)137. 125X72X4130.1

9、02X45138. 728X79 十 272X79131.32X125X25139. 8. 59+2. 57+3. 43+5. 47132.43X99+43140. 49. 62+27.17 - 19. 62141. 1546 - (546 - 239)149. 2008X - 2006X20082007.17 / 3010 / 3010 / 301數(shù)學(xué)簡便運算142.150. 24. 87 - 0. 53 - L 47143. 1999-999X999.151. 50X (旦 J 一至)10 5 25144. 4.37X6.3+4.37X3.7152- °-375Xt444145.

10、 2.644-1.25-?0.8153. 7.5+2.7+2.7+2.5+43146. 10.2X0.45.154. 7.9 - 3.27 - 0.73+1.1147. 3. 5%X9. 9155. 72X1252 6 12 20 30156. (80+4) X125165. 1.25X32X2.5157. 67X88+67X11+6719 / 3011 / 3011 / 301數(shù)學(xué)簡便運算158. 203X15.166. 4X3. 5+4.8X7-1- 480%52159. 4392 - 2997167.(5- 1.8) -? (1. 15+i?) X520160. 2.5X32X 1.25

11、168. 3333X224+6666X368.161.169. 395 - 283+154+246 - 117162. 13x2出7 7170. 8795 - 4998+2994 - 3002 - 2008171. 1999+999X999163. 94- (20.75 - 9.5) X0.4164.172. 38X25X6.181. 16X125173. 2.06X101182. 19004 + 25.174. 0. 25X125X0. 3220 / 3012 / 3012 / 30數(shù)學(xué)簡便運算175. 1.25X8.8183. 8.35+3.8 - 2.35184. 15.4- (5.4+

12、23)176. 31.8X2. 5+31.8X7.5.185.98X45177. 19X8X125178. 38+129+71186. 16X125X25179. 1756 - 398187. 12X69 - 69X2180. 406X201188. (20+8) X25.189. 9+99+999+9999+99999：197. 653 - 197190. 1 - 2+3 - 4+5 - 6+- 1992+1993.198. 125X17 - 125191. 36X11；199. 235X99192. 246X11.193. 678+ (354+322)200. (1300 - 520) -

13、M3201. 67X21+18X21+85X7921 / 3013 / 3013 / 30 J數(shù)學(xué)簡便運算202. 222222X999999.194. 283+147+17+1653195. 384 - (37+184)203. 1 過 xU，25 20196. 2904 - 1327 - 173204. 5 20 20205.0.8X7.3 - 63X20.08213.23 X罵14 X”3939206.65.5 -4.29+24.6 - 5.71214. 38. 4 X 187 - 15. 4 X 384+3. 3 X 16=22 / 3014 / 3014 / 30數(shù)學(xué)簡便運算207.

14、208.99999X22222+33333 X 33334216. 2009 : 200您更2010209.2003 X 2004+2004 X 2004 - 2003 X 2004217. 91-9在999i+99991-仁5 555 5210.2.8X （1+-五） 7 2S218. 4. 034-12.5.QQ1991+1989+2000+1995+2011 +2005+1998+1993.215.與三-（0. 16+1白）-1.841515211.219. 1997+1998+1999+2001212.9.81X10%+0.5 X98.1 +0.049 X 981220. 3425 -

15、 188 - 212 - 25229. 1.25X1.25X32221. 567X999+567X224 / 3015 / 3015 / 30I數(shù)學(xué)簡便運算222. ( 91X48X75 ) + ( 25X13X16)230.15 17X17.223. -X3+X5+X10181818231. 25 X 99+25224.999X7+111X7232. 75 X 75+75 X 25225. 97 XA96233. 64X125226.(A+_1+_L+_L)X20022 7 11 13234. 17+64+83+36235. 1200- 128 - 72227. 8.5X-3-0. 75X5

16、t6.5-?1A43228.專磋喏99哈99娛.236.3000125 + 8.237. . 65X8. 7+6. 5X0. 23 - 0. 65238.彳下出喉二?25 / 3016 / 3016 / 30數(shù)學(xué)簡便運算X2,答案：1. (0. 86+0. 86+0. 86+0. 86) 125,=0. 86X (4X25),=0. 86X100,=86：2. 4 + l?+6xW35=(4+6) X 旦5noxW5=6：3. 1254- (50 + 8),=125X84-50,=1000 : 50,=20：4. 7.6X、L9-L9X (L9-L9),2=7.6xA-i.9- 1.9X0,2

17、=7.6X1+L9,2=25. 999X999 - 2X999+1,=(1000 - 1) X (999 - 2) +1,=(1000 - 1) X 997+1,=1000X997 - 1X997+1,=997000 - 997+b=9960046. 1.25X0. 25X0. 05X64,=1.25X0. 25X0. 05X (8X4X2),=(1.25X8) X (0.25X4) X (0. 05X2),=10X1X0. 1,=1:7. 20. 06X65+380X2. 006 - 2. 006X30,=20. 06X65+ (380- 30) X 2.006,=20. 06X65+350

18、X2. 006,=20. 06X65+ (350-4-10) X (2. 006X10),=20. 06X65+35X20. 06,=20. 06 X (65+35),=20. 06X100,=20068. 8 442=(-T，8 4 4 42= d-JL)8 644X2, 64工=329. 22x23, 24X (24-1),24&X24 -空2424=23 -”24二2嗑：10. 3是-15. 38+61. 25 - 3. 62, 4=38. 75+61. 25 - (15.38+3.62),=100- 19,=81；11. 17. 98+2.5X0.3- 18-M. 5>=

19、17. 98+0. 75 - 12,=18. 73-12,=6. 73：12. Cx&+«lx&, 4 7xi, 7713. (-I+) 4-L.8 1616=2+b=314. 4. 76+5*5. 24, o=4. 76+5. 24+在8二 10+走，8二 15至，815. 3提一 (0.16+13) -1.84>26 / 3017 / 3017 / 301數(shù)學(xué)簡便運算27. 3. 7X+5. 3X0. 75+. 44=(3. 7+5. 3+1) X0. 75,=10X0. 75,=7.5；28. 9. 9+99. 9-999. 9,=(9. 9+0. 1)

20、+ (99.9+0. 1) + (999. 9+0. 1)=10+100+1000 - 0. 3,=1110-0.3,=1109.7：29. 6.8-?4- 1.2X25%t4-?X0. 25.5=6.8x1- 1. 2x1+4. 4x1444=(6. 8- 1.2+4. 4) xX4=ioxX4=2.530. 6. 3+6. 44+2. 7+3. 56,=(6. 3+2.7) + (6. 44+3.56),=9+10,二 19：31. 15.35 - (5. 35+7.2),=15. 35 - 5. 35 7. 2,=10-7.2,=2.8；32. 600 + 12,-0. 1X3,二四一0

21、.16-1衛(wèi)-L84,11 11=(足-1且)-(0. 16+1.84),11 11=2-2,=0：16. 2.8- (0.43+2+1?)， J J=2.8- 0. 43+ (1+1-2), 3 3=2. 8 - 0. 43+2,=2.8-2. 43, =0. 37；17. 9. 56-3-2455二9.56-(遼-馮，5 5二9. 56-6, =3. 5618. 22.7X1.25X0.8, =22. 7 X (1.25X0.8), =22.7X1, =22. 7；19. 3.91X2. 8+6. 09X2.8, =(3.91+6. 09) X2.8, =10X2.8, =2820. 23

22、.4X16 - 23.4X6, =(16-6) X23.4, =10X23.4, =234：21. 20-5- 5. 75 - 14. 25. 6=2心-(5.75+14. 25), 6二2走-20, 6_5 622. 1.25X0.25X32, =1.25X0. 25X8X4, =1.25X8X (0. 25X4), 二10X1,=10：23. 56X (至一三工)，7 8 28二56x2- 56X至+56X工7828=24 - 21+2,=24. 0. 279X258+0. 742X279,=279X0. 258+0. 742X289,=279X (0. 258+0. 742),=279X

23、1,=279：25. 13+28+11 + 27+15+ 28+3827,*乂24乂15 令 X24X15,=150+24,=174；27 / 3018 / 3018 / 301數(shù)學(xué)簡便運算=6004- (6X2),-600-r 64-2,=100 + 2,=50：33. 67X102, =67X (100+2), =67X100+67X2,=25942= 25-勺438. 1.3 - 3.79+9.7 - 6.21,=(1.3+9. 7) - (3. 796.21),=11-10,=6700+134, =6834=1：39. 3.644+4. 36X0.25,34. 4.85-|+5,153

24、，=3. 64X-1+4. 36X-i,=10 - 1,=4. 85+5. 15 -(至 9=(3. 64+4. 36)X1二9：35. lx (-4-3. 6+6.15X3-2), 94 185 x (4. 75X里-3.6-6. 15X3.6),95Xl <4.75+6. 15-1) X3. 6,9=8xAt4二2；40.良：(至-1)X (I-A),jX9.9X3.6, 9=3. 96：96 2一4二1乂3一 八，9 3 8-4*33 8：241.改X4.25+41xL羌即49-2一哆37. W+3各5裊7擊64=(9+1)6 6=10x11,4-8542.3。)X4X9,9 12

25、=(1+3+5+7+9) + (二)+ (工二)二,6 1220 3042=25+ (2二)+ (衛(wèi)二)J,12 1260 6042=25+3工，12 60 42=25+ (且二)二，12 1242二 25+1工，3 42=(工工)X (4X9),9 12=(工-工)X36,9 12rAx36 -X36,912=4-3,=1：43. 1+2+3+4+49+50,=(1+50) + (2+49) + (3+48) + (25+26),=51+51+51+51+51,=51X25,29 / 3019 / 3019 / 30數(shù)學(xué)簡便運算56. 194+501,=194+500+1,=695；57,

26、627 - (427+189), =627 - 427 - 189,=11：58. 630 + 14, 二630 : 72,=90+2,=45；59. 125X25X32,=(125X8) X (25X4),=1000X100,=100000：60. 210 + 6：5,=2104- (6X5),=210:30,=761. 125X32,=125X8X4,=1000X4,=4000：62. 6404-54-8, 二640小(5X8),=640-40,=16；63. 653 - 98, 二653 - 100+2,=453+2,=455；64. 944+102,=944+100+2,=1044+2

27、,=104665. 25X79X4=25X4X79=100X79=790066. 8X166X25 =8X25X166 =200X166=3320067. 50X25X4X3=(25X4) X (50X3)=100X150=1500068. 8X (25X15)=8X25X15=200X15=127544. 4.8X0. 25,=1.2X (4X0. 25),=1.2Xb=1. 2：45. 2. 33X0.5X4,=2. 33 X (0.5X4),=2. 33X2,=4. 66；46. 1.2X2. 5+0. 8X2. 5,=(1.2+0. 8) X2. 5,=2X2.5,=5：47. 3.

28、7 ; L 254-8.=3. 74- (1.25X8),=3. 710,=0. 3748. 43. 69. 8+6.4,=9.8+ (43. 6+6. 4=9.8+50,=59. 8；49. 17.3X0. 25X8,=17. 3X (0. 25X8),=17.3X2,=34. 6；50. 2.31X1.5+1.5X7. 69.=(2.31+7. 69) X1.5,=10X1.5,=1551. 10. 24 - 6. 67 - L 33,=10. 24 - (6. 67+1.33),=10. 24-8,=2. 24；52. 32000 + 125 + 8,=320004- (125X8),=

29、32000-1000,=32；53. 7.31+15. 05+2. 69+4.95,=(7.31+2.69) + (15. 05+4.95),=10+20,=30：54. 47X101,=47+ (100+1),=47X100+47,=4700+47,=474755. 573 - 298,=573 - 300+2,=275：31 / 3020 / 3020 / 301數(shù)學(xué)簡便運算=(5. 39+4.61) + (12應(yīng)), 7 7=10+2,=12；85. 0. 588X l-+4X9. 412+2X0. 588,=0. 588 X (12+2)+4X9.412,3 3=0. 588X4+4X

30、9.412,=4X (0. 588+9.412),=300069. (250X72) X4 =250X4X72=1000X72=7200070. 5X25X13X40X20=(25X40) X (5X20) X13=1000X100X13=130000071. 7350:25,=(7350X4) + (25X4), =29400-100, =294：72. 54X101, 二54X100+54,=5454：73. 227+364+146+173,=(227+173) + (364+146),=400+510,=910：74. 5604 - (723+1604),=5604 - 1604 - 7

31、23,=32771.67+0. 3375. 88二 X (1.67+0. 33 ), 822, 8,3：476. 999X667+667X1, =667X (999+1), =667X1000, =66700077. 2004 X型蛆，2003=(2003+1) X 型退，2003=2003x222+i x?002, 20032003二2002+空里，2003二2002型空：200378. 81 - (3.81 - 1.65) +2. 25, =81 - 3. 81+1. 65+2. 25,=(81 - 3.81) + (1.65+2. 25),=77. 19+3. 9,=81.09：79.

32、24 X (國-L2),6 4 3=24X- 24X-1+24X-?,643=20 - 6+16,=14+16, =3080. (2) X24, 3 4=_?X24+X24t34=16+6, =22：81. WL+理X型93 f 7 93_3葭1 1 乂 26 93 7 7 93=(以藥xl93 937&X支 93 7, 3-3T82. 2.5X3.2X1.25,=(2.5X0.4) X (8X1.25), =1X10, =10；83. 4.05 - (2.05+至)，27=4. 05 - 2. 05 -二,27二2 -王,27-22-1：2784. 5.39+12+4.61+a,77

33、 二4X10, =4086. 45X98+45X2, =45 X (98+2),=45X100, =4500：87. 452 - (152+240), =452 - 152 - 240,=60：88. 99X27,=(100 - 1) X27, =2700 - 27,=2673：89. 1120 + 16 + 7, =11204- (16X7), =1120-4-112, =1090. 113X36 - 13X36, =36X (113- 13), =36X100, =3600；91. 179 - 245+321 - 155, =(179+321) - (245+155), =400 - 40

34、0,=092. 1. 24+14. 95+8. 76 - 4. 95,=(1.24+8. 76) + (14. 95- 4. 95), =10+10,=20：93. 52.7 - 5. 27 - 2.7, =(52.7 - 2.7) - 5.27, =50 - (5+0.27), =50 - 5 - 0. 27, =45 - 0. 27, =44. 73； 94. 35X201,=35X (200+1), =35X200+35, =7000+35, =7035；95. 4500 + 25 + 4, =4500+ (25X4), =4500:100, =45：96. 125X32,=(125X8

35、)義4,二1000X4, =4000；97. 654X99+346X99,=(654+346) X99, =1000X99, =99000 98. 56X12.5, =7X (8X12.5),=7X100,=700：99. 14.6- (4. 6+7. 2),=14.6-4.6-7.2,=10-7.2,=2.8；100. 99X99+199, =99X99+99+100,=99X (99+1) +100, =99X100+100, =9900+100, =10000101. 0. 125X0. 25X8X4,=(0. 125X8) X (0.25X4)，=1X1,=1：102. 1927 -

36、528 - 472,=1927 - (528+472),=1927 - 1000,=927103. (1+!-1>)X105,3 5 15=Ax 105+lx 105+Ax 105,3515=35+21+7,=56+7,=63：104. xl+25%X 25xX7 477_3乂 1 1乂 2 1乂 17 4 4 7 4 7二(苣+2+工)x支7 7 747 4, 3：14105.遙-走-遙7 9 7 9 7=(2至+14-3苣)+ (1&是),7 7 79 9=(4-3) +5, 733 / 3022 / 3022 / 302數(shù)學(xué)簡便運算二+5,7=5-：7106. 3.7X99

37、+3.7,=3. 7X (99+1),=3.7X100,rAx 12 - Ax 12+1x1236=4 - 2+3=：115.式X昌工小號4 8 4 57乂5 1乂5Z - ZX=370107. 1.2X2. 5+2. 8X2. 5,=(1.2+2. 8) X2. 5,=4X2.5,=10：4 8 4二(4 4=2X至835 / 3023 / 3023 / 302數(shù)學(xué)簡便運算108. 4. 8X2.5,=(4X1.2) X2.5,=(4X2.5) XI. 2, =10X1.2, =12=114116. 7. 25 - 3+3. 75 6, =<7. 25+3. 75) - (3+6),

38、=11 -9,109. 4. 05 - 2. 86 - 0.14, =4. 05 - (2. 86+0. 14), =4. 05 - 3,=1. 05；HO. 7lX|0.4X71= 7-1x(0. 6+0.4),=2.117. 49X (J+l) X25,7 5=49x11x25,35=595；118-導(dǎo)b111. 2. 25X3.14X4+3. 14,=2. 25X4X3.14+3. 14, =9X3. 14+3. 14>=(9+1) X3.14,=10X3. 14,-113xt-465119./x與lix生金13 5 13 5 5=(工 Ji - 1)X_i13 135=31.4；

39、112.-115(二-)X17X15,15 51X15X17-! X17X15,51-111 11 5=15-4I .5=17-5, =12113. 6.3X8. 7+8. 7X3. 7=(6. 3+3.7) X8.7 =10X8.7=87：120. -ixi2.5X8X0.4, 4=<-jX8)X (12.5X0.4),=2X5,=10；121. 24X (旦一)X12,8 6=(24x3- 24X A) X12, 86=(9-4) X12, =5X12, =60122. 25X0.32X1.25, =25X0.4X0.8X1.25, =(25X0.4) X (0.8X1,25), 二

40、10X1,=10：123. 0. 37X79+3.7X2. 1,=3. 7X7. 9+3. 7X2. 1,=3. 7X (7. 9+2. 1), =3. 7X10.=37：124. 2011 + 2011型11+-2012 2013二2011+.加比 2012+2011,上20122013=2011X20122011X (2012+1)12013=1：127. 1000+999X999, =1000+999 X (1000 - 1), =1000+999X1000 - 999X1, =1000+999000 - 999, =1000000 - 999, =999001128. 178.4 -

41、45.3 - 54.7, =178. 4 - (45. 3+54.7), =178.4 - 100,=78.4：129. 456 - (256 - 144), 二456-256- 144,=200 - 144,=56；130. 102X45, =100X45+2X45, =4500+90, =4590：131. 32X125X25,=(8X125) X (4X25),=1000X100,=100000：132. 43X99+43, =(991) X43, =100X43, =4300：133. (40+8) X25, =40X25+8X25, 二1000+200,=1200：134. 73X9

42、9,=73X100 - 73X1,=7300 - 73, =7227：135. 54X11 - 54,=(11 - 1) X54, =10X54,=540136. 301X79, =(300+1) X79, =300X79+1X79, =23700+79, =23779：137. 125X72X4, =(125X4) X72, =500X72, =36000：138. 728X79 十 272X79, =79X (728+272),二79X1000, =79000：139. 8. 59+2. 57+3.43+5. 47, =8. 59+ (2. 57+3.43) +5. 47, 二8. 59-

43、6+5. 47,=20. 06：140. 49. 62+27. 17 - 19.62, =49. 62 - 19. 62+27.17, =30+27.17,37 / 3024 / 3024 / 302數(shù)學(xué)簡便運算二2乏：6149. 2008X - 2006X20082007,=2008 X (2007X10000+2007+1) - 2006 X (2008X 100002007)>=2008X2007X10000+2007X2008+2008 - 2006X2008 X 10000 - 2006X2007,=2008X100002X2007+2008,=20080000+4014+20

44、08,=20086022150. 24. 87 - 0. 53 - 1. 47,=24. 87 - (0. 53+1.47),=24.87 - 2,=22. 87：151. 50X (且 J - 上)，10 5 25=50xA|x50- 50xA, =15+20 - 12, =35 - 12, =23：152. 0. 375x15+ 一工. 義2 8 2 3 _3、電3_ 13 8 2 8 2 8_( 15.1 1 x y 3-(+1 - -) x-, 228二8x2 8=3153. 7. 5+2. 7+2. 7+2. 5+4. 3=(7. 5+2.5) + (2. 7+4.3) +2.7,

45、=10+7+2. 7, =19.7： 154. 7.9 - 3. 27 - 0. 73+1.1 =7. 9+1.1 - (3. 27+0. 73),=9-4, =5； 155. 72X125 =9X8X125, =9X (8X125),=9X1000, =9000； 156. (80+4) X125 =80X125+4X125, =10000+500, =10500： 157. 67X88+67X11+67 =(88+11+1) X67,=57.17： 141. 1546 - (546 - 239),=1546 - 546+239,=1000+239, =1239142. -Ix-L+Ax-L

46、-Ax-k+AxA, 2 77 3 77 4 77 5 77_(1 1乂 1- k T-T-+- ) X> 234577二(皿雪芟+烏xX60 60 60 6077-77乂 1 60 77一 1與143. 1999+999X999,=(1000 - 1) X 999+1999,二999000 - 999+1999, =999000+1000, =1000000144. 4.37X6.3+4.37X3.7,=4. 37X (6. 3+3.7),=4. 37X10,=43. 7；145. 2.64 + L25 : 0.8,=2. 64+ (1.25X0.8),=2. 64+1,=2. 64：

47、146. 10.2X0.45,=(10+2) X0.45,=10X0. 45+2X0. 45,=4. 5+0. 9, =5. 4.147. 3.5%X9.9,=0. 035 X (10 - 0.1),=0. 035X10 - 0. 035X0. b=0. 35 - 0. 0035,二0. 3465；148. 11+3工+51+7工+9-L2 6 12 20 30 =1+1+3+5+7+9+,26 12 20 30=(1+3+5+7+9) + (1+1+工+工+工)，2 6 12 20 30 1_1_ L 1. 1) 223344556=25+ (1-1), 6=25+3638 / 3025 / 3025 / 302數(shù)學(xué)簡便運算161.=100X67, =6700.158. 203X15 =(200+3) X15, =200X15+3X15, =3000+45, =3045159. 4392 - 2997,=4392 - 3000+3, =1392+3,=1395：160. 2.5X32X1.25,=(2.5X4) X (8X1.25),二10X10, =100：7乂 12: 2 二