简便运算的练习题和答案

1、(1)乘法交换律：aXb=bXa38X25X442X125X8运算定律练习题乘法结合律：(aXb) Xc=aX (bXc)25X17X4(25X125) X (8X4)1#49X4X538X125X8X3(125X25)X45 X289X2(125X12) X8125X (12X4)#125X2425X28(2) 乘法交换律和结合律的变化练习125X64125X8844X25(3)加法交换律：a+b=b+a加法结合律：(a+b) +c=a+ (b+c)357+288+143158+395+105167+289+33129+235+171 + 165378+527+73169+78+2258+3

2、9+42+61138+293+62+107(4)乘法分配律：(a+b) Xc=aXc+bXc正用练习(80+4) X25(20+4) X25(125+17) X825X(40+4)15X (20+3)(5)乘法分配律正用的变化练习：36x325x4139x101125x88201X24(6)乘法分配律反用的练习：34 X 72+34 X2835 X 37+65 X 3785 X 82+85 X1825X97+25X376X25+25X24(7)乘法分配律反用的变化练习：38X29+3875X299+7564X199+6435X68+68+68X64思考题：(8)其他的一些简便运算。8004-2

3、560004-12536004-84-574X9958X101-58【思路导航】在除法里，被除数和除数同时乘或除以一个相同的数，商不变。325专 25=(325x4) 4- (25x4)=13004-100=13【练一练 1】(1) 4504-25(2) 525W25(3) 3500M25(4) 10000625(5) 495002900(6) 90004-2252#【经典例题二】计算25x125x4x8【思路导航】如果先把25与4相乘，可以得到100,同时把125与8相乘，可以得到1000； 再把100和1000相乘就可以了。运用了乘法交换律和结合律。25x125x4x8=(25x4) x

4、(125x8)=100x1000=100000【练一练 2】(1) 125x15x8x4(2) 25x24(3) 125x16(4) 75x16(5) 125x25x32(6) 25x5x64x125【经典例题三】计算：(1) 125x34+125x66(2) 43x11+43x36+43x52+43【思路导航】利用乘法分配律来计算这两题(1) 125x34+125x66(2) 43x11+43x36+43x52+43=125x (34+66)=43x (11+36+52+1)=125x100=43x100=12500=4300【练一练3】计算下面各题：(1) 125x64+125x36(2)

5、 64x45+64x71-64x16(3) 21x73+26x21+21【经典例题四】计算(1) (360+108)三36(2) “2+3丰2+5三2+7*2【思路导航】两个数的和、差除以一个数，可以用这个数分别去除这两个数，再求出两个商 的和(差)。利用这一性质，可以使计算简便。(1) (360+108) 4-36(2) “2+3三2+5三2+7三2=360236+108三36= (1+3+5+7)三2=10+3=164-2=13=8【练一练 4】(1) (720+96) *24(2) (4500-90) 4-45(3) 634221(4) 881U89(5) 734-36+1054-36+

6、1464-36(6) (10000-1000-100-10) 4-10【经典例题五】158x6279x3【思路导航】在乘除混合运算中，如果算式中没有括号，计算式可以根据运算定律和性质调 换乘数或者除数的位置，只要计算：数字跟着前面的符号一起移动。158x6279x3=158三79x61x3=2x61x3=366【练一练5】计算下面各题：(1) 238x364-119x5(2) 138x27丸9x50(3) 624x48312三8(4) 406x312104三203【经典例题六】计算下面各题：(1) 103x964-16(2)200三(254)【思路导航】这两道题都是乘除法混合运算，我们可以根据

7、这两道题的特点，采用加括号和 去括号的方法，使计算简便。可以概括为：括号前是乘号，加、去括号不改号，括号前是除 号，田、去括号要改号。(1) 103x96-16(2) 20哄(252)=103x (964-16)=200-25x4=103x6=8x4=618=32【练一练6】计算下面各题：(1) 612x366/83(2) 10004- (1254)(3) (13x8x5x6)三(4x5x6)(4) 241x345278丰345x (678241)【经典例题七】计算：(1) 68x62(2) 85x85【思路导航】这两题的形式叫做“头同尾合十”它们的计算方法是：先用两个因数的个位数相 乘，并把

8、积直接写在末尾，如果积不满10,十位上要补写0,然后再将两个因数的十位数乘 它本身加1的和，积写在两个个位数积的前面。(1) 68x62第一步8x2=16,第二步6x (6+1) =42,合起来是4216(2) 85x85第一步5x5=25,第二步是8x (8+1) =72,合起来是7225【练一练 7 (1) 23x27(2) 46x44(3) 55x55(4) 91x99【经典例题八】计算：26x11【思路导航】一个两位数乘11的方法是：用两位数的头作积的头，用两位数的尾作积的尾, 用这个两位数的两个数字之和作积的中间数(如果相加满十，则把和的十位数“1”加到头上。 26x11第一步2作积

9、的头，第二步6作积的尾，第三步2+6=8作中间，合起来是286。【练一练 8计算(1) 53x11(2) 39x11(3) 65x11(4) 98x11【经典例题九】计算：358x11【思路导航】三位数乘11,用三位数的头作积的头，用三位数的尾作积的尾，用三位数前两 位数字组成的数加厚两位数字组成的数的和作积的中间数。358x11,第一步用3作积的头，第二步用8作积的尾，在用35+58二93,合起来是3938。【练一练9】计算(1) 353x11(2) 654x11(3) 896x11【练一练 1 (1) 4504-25(2) 5254-25(3) 3500M25(4) 10000-625(5

10、) 49500-900(6) 9000225【练一练 2】(1) 125x15x8x4(2) 25x24(3) 125x16(4) 75x16(5) 125x25x32(6) 25x5x64x125【练一练3】计算下面各题：(1) 125x64+125x36(2) 64x45+64x71-64x16(3) 21x73+26x21+21【练一练 4】(1) (720+96) -24(2) (4500-90)二5(3) 63424-21(4) 881U89(5) 7336+1054-36+1464-36(6) (10000-1000-100-10) 10【练一练5】计算下面各题：(1) 238x3

11、64-119x5(2) 138x2769x50(3) 624x483128(4) 406x312104-203【练一练6】计算下面各题:(2) 1000m (125W4)(3) (13x8x5x6)专(4x5x6)(1) 612x3662183(4) 241x345m678m345x (678241)【练一练7】(1) 23x27(2) 46x44 55x55(4) 91x99【练一练 8】计算(1) 53x11(2) 39x11(3) 65x11(4) 98x11【练一练 9】计算(1) 353x11(2) 654x11(3) 896x11简便计算专题训练158+262+138375+219

12、+381+2255001 -247-1021 -232(181+2564) +2719378+44+114+242+222276+228+353+219(375+1034)+(966+125)(2130+783+270)+10仃99+999+9999+999997755-(2187+755)2214+638+2863065-738-1065899+3442357-183-317-3572365-1086-214497-2992370+19953999+49861883-39812x2575x24138x25x4(13x125)x(3x8)(12+24+80)x50简便计算练习题2704x252

13、5x32x12532x(25+125)88x125102x7658x98178x101-17884x36+64x8475x99+2x7583x102-83x298x199123x18-123x3+85x12350x(34x4)x325x (24+16)178x99+17879x42+79+79x577300-25-48100-4-75168004-12030100210032000-40021500-1257(300+6)x1225x(4+8)125x(35+8)(13+24)x884x101504x2578x10225x20499x6499x16638x99999x9949700-r7001

14、248-243150+154800-25简便计算练习题32356- (1356-721)1235-(仃80-1665)75x27+19x2 531x870+13x3104x(25x65+25x28)99X13+1325+199X2532X16+14X3278X4+78X3+78X3125X32X825X32X12588X12572X1253600+25+4简便计算练习题48100-4-753000-125-81250+25+5278+463+22+37732+580+2681034+780320+102425+14+186214- (86+14)787- (87-29)365- (65+118

15、)455- (155+230)576-285+85825-657+57690仃7+77755-287+871200-624-762100-728-772273-73-27847-527-273871-299157-99363-199968-599178X101 -17883X102-83X217X23-23X735X127-35X16-11X35简便计算练习题5600-60-5-1520X4-20X4736-35X2025X4-25X498-18X5+2556X8-56X8280-80-r 412X6-12X6仃 5-75-2525X8-25X880-20X2+6036X9-36X9容易出错类

16、型（共五种类型）36-36-6-625X8-T (25X8)100+45-100+4515X97+39100+1-100+148X99+11000+8-1000+85+95X28102+1-102+165+35X1325+75-25+7540+3604-20-1013+24X8672-36+64324-68+32100-36+6426X39+61X26简便计算练习题6356X9-56X999X55+5578X101-7852X76+47X76+76134X56-134+45X134184+98695+202864-199738-301380+476+120(569+468) +(432+131

17、)704X2548X52X2-4X4825X23X (40+4)999X999+1999256-147-53373-129+29189- (89+74)28X4X25125X32X259X72X1257204-164-5简便计算练习题7630+42456- (256-36)102X35 98X42158+262+138375+219+381+2255001-247-1021-232(181+2564) +2719378+44+114+242+222276+228+353+219(375+1034) + (966+125)(2130+783+270)+101799+999+9999+999997

18、755-(2187+755)2214+638+2863065-738-1065899+3442357-183-317-3572365-1086-214497-2992370+19953999+498简便计算练习题81883-39812X2575X24138X25X4(13X125)X(3X8)(12+24+80) X501298X199123X18-123X3+85X12350X(34X4)X325X (24+16)178X99+17879X42+79+79X5773004-254-48100+4一 75158+262+13825X32X12532 X (25+125)88X125102 X

19、76178X101-17884X36+64X8475X99+2X75(2130+783+270)+101799+999+9999+999997755 - (2187+755)(2130+783+270)+101799+999+9999+999997755 - (2187+755)简便计算练习(2130+783+270)+101799+999+9999+999997755 - (2187+755)12484-2431504-1548004-25215004-125375+219+381+2255001-247-1021-232(181+2564) +2719(2130+783+270)+1017

20、99+999+9999+999997755 - (2187+755)(2130+783+270)+101799+999+9999+999997755 - (2187+755)(375+1034) + (966+125)378+44+114+242+222276+228+353+219(2130+783+270)+101799+999+9999+999997755 - (2187+755)2214+638+2863065-738-1065899+3442357-183-317-3572365-1086-214497-2992370+19953999+4981883-39812X25简便计算练习题

21、1075X24138X25X4(13X125)X(3X8)(12+24+80)X50704X2525X32X12532X (25+125)88X125102X7658X98178X101-17884 X 36+64 X8475 X 99+2 X 7583X102-83X298X199123X18-123X3+85X12350X(34X4)X325X (24+16)178X99+17879X42+79+79X57215004-12573004-254-481004-44-75168004-12015简便计算练习题11(a+b) + c = a + (b+c)2. 73 + 0.89 + L274

22、. 37 + 0.28 + 1.63 + 5. 72 ab_c = a (b+c)9.3 - 5.26 - 2.7410 一 0.432 2. 56814. 9一 (5.2+4.9)18.32 - 5.47 - 4. 32(a X b) Xc = a X(b X c)25 X 6.8 X 0.040.25 X 32 X 0.1256.4 X 1.25 X 12.5(a+b) = cXa +cXb0.45 X 2010.58 X 10.150.2 X 994.7 X 9.916#简便计算练习题123.28 X 5.7 + 6.72 X 5.72.1 X 99 + 2-123 X 0.1 + 2.

23、3 X 9.90.18 +4. 26 一0 18 +4. 260. 58 X1.3 十 0. 58 XL 37.3 4-4 + 2.7 X 0.253.75 X 0.5 - 2.75 4- 25.26 X 0.125 + 2. 74 十 8#930 4- 0.6 4-563.4 4- 2.50.4(7.7 + 1.54) -r 0.76. 9+4. 8+3.1简便计算练习题1315. 89 + (6. 75-5. 89)7. 85+2. 34-0. 85+4. 6635. 6-1. 8-15. 6-7. 213. 75- (3. 75+6. 48)47. 8-7. 45+2. 5566. 86

24、-8. 66-1. 340. 25X1 & 2X40. 25 X 32 X0.1252 .5 X (4 +0. 4)(1.25-0.125)X84.8X100.1a 4- b 4- c6.3 * 1.8(b X c)9.5 十(1.9 X 8)12.8 三(0.4 X L6)4.2X9956. 5X9. 9+56. 57. 09X10. 8-0. 8X7. 093. 83X4. 56+3. 83X5. 443. 65X4. 7-36. 5X0. 375. 4X11-5.413.7X0. 25-3. 7-410.7X16.1-1.1X10.7 +10.7 X5简便计算专题训练17#158

25、+262+138375+219+381+2255001-247-1021-232#(181+2564) +2719378+44+114+242+222276+228+353+219(375+1034)+(966+125)(2130+783+270)+101799+999+9999+999997755-(2187+755)2214+638+2863065-738-1065899+3442357-183-317-3572365-1086-214497-2992370+19953999+4981883-39812x2575x24138x25x4(13x125)x(3x8)(12+24+80)x507

26、04x25简便计算练习题225x32x12532x(25+125)1988x125102x7658x982356- (1356-721)1235- (1780-1665)75x27+19x2 52356- (1356-721)1235- (1780-1665)75x27+19x2 5178x101-17884x36+64x8475x99+2x7583x102-83x298x199123x18-123x3+85x12350x(34x4)x325x (24+16)178x99+17879x42+79+79x577300-25-48100*75168004-12030100210032000-400

27、21500-12549700-r7001248-243150-154800-25简便计算练习题32356- (1356-721)1235- (1780-1665)75x27+19x2 531x870+13x3104x(25x65+25x28)(300+6)x1284x10199x6499X13+13125X32X83600+25+41200-624-7625x(4+8)125x(35+8)(13+24)x8504x2578x10225x20499x16638x99999x9925+199X2532X16+14X3278X4+78X3+78X325X32X12588X12572X125简便计算练

28、习题48100-4-753000125-81250-25-52100-728-772273-73-27847-527-273278+463+22+37732+580+2681034+780320+102425+14+18622214- (86+14)787- (87-29)365- (65+118)455- (155+230)576-285+85825-657+57690-177+77755-287+87871-299157-99363-199968-599178X101-17883X102-83X217X23-23X735X127-35X16-11X35简便计算练习题5容易出错类型（共五种类

29、型）600-604-1520X4-20X4736-35X2025X4-25X498-18X5+2556X8-56X8280-80- 412X6-12X6175-75-2525X8-25X880-20X2+6036X9-36X936-36-6-625X8- (25X8)100+45-100+4515X97+3100+1-100+148X99+11000+8-1000+85+95X28184+98695+202864-199738-301380+476+120(569+468) + (432+131)704X25256-147-53373-129+29189- (89+74)102+1-102+1

30、65+35X1325+75-25+7540+36020-1013+24X8672-36+64324-68+32100-36+6426X39+61X26简便计算练习题6356X9-56X999X55+5578X101-7852X76+47X76+76134X56-134+45X13448X52X2-4X4825X23X (40+4)999X999+199928X4X25125X32X259X72X125720-?16-r5简便计算练习题76304-42456- (256-36)3999+498简便计算练习题81883-39812X2575X24138X25X4(13X125)X(3X8)(12+

31、24+80) X5025X32X12532X (25+125)88X125102X76102X35 98X42158+262+138375+219+381+2255001-247-1021-232(181+2564) +2719378+44+114+242+222276+228+353+219(375+1034)+(966+125)(2130+783+270)+101799+999+9999+999997755-(2187+755)2214+638+2863065-738-1065899+34423571833173572365-1086-214497-2992370+1995178X101-

32、17884X36+64X8475X99+2X7598X199123X18-123X3+85X12350X(34X4)X37300一 25 一 48100*4*75158+262+13812484-24简便计算练习题93150+1548004-2521500-12525X (24+16)178X99+17879X42+79+79X57375+219+381+2255001-247-1021-232(181+2564) +2719378+44+114+242+222276+228+353+219(375+1034)+(966+125)26#(2130+783+270)+101799+999+999

33、9+999997755-(2187+755)2214+638+2863065-738-1065899+344#2357-183-317-3572365-1086-214497-2992370+19953999+4981883-39812X25简便计算练习题1075X24138X25X4(13X125)X(3X8)#(12+24+80) X50704X2525X32X12532X (25+125)88X125102X7658X98178X101-17884 X 36+64 X8475 X 99+2 X 7583X102-83X298X199123X18-123X3+85X12350X(34X4)

34、X325X (24+16)178X99+17879X42+79+79X57215004-12573004-254-4(a+b) + c = a81004-44-75简便计算练习题11 + (b+c)16800十1202. 73 + 0.89 + L274.37 + 0.28 + L63 + 5.72abc = a (b+c)10 一 0.432 2. 5689.3 - 5.26 - 2.7414. 9- (5.24-4.9)18. 32 - 5.47 - 4. 3225 X 6.8 X 0.040.25 X 32 X 0.1256.4 X L 25 X 12-528c X (a+b) = cX

35、a + cXb50.2 X 994.7 X 9.90. 45 X 2010. 58 X 10.1简便计算练习题123.28 X 5.7 + & 72 X 5. 72.1 X 99 + 2.123 X 0.1 + 2. 3 X 9.90.18 +4.26 -0.18 +4. 260. 58 X1.3 4- 0. 58 XL 37.3 4-4 + 2.7 X 0.253.75 X 0.5 - 2.75 4- 25.26 X 0.125 + 2 74 十 86.3 十 1.8(b X c)9.5 4- (1.9 X 8)12.8 十(0.4 X L 6)930 4- 0.6 4-563.4

36、三 2.5 弓 0.4(7.7 + L 54) 4-0.76.9+4.8+3.1简便计算练习题1315. 89+(6. 75-5. 89)1. 85+2. 34-0. 85+4. 6635. 6-1. 8-15. 6-7. 213. 75- (3. 75+6. 48)47. 8-7. 45+2. 5566.86-8. 66-L340. 25X16.2X40. 25X32 X 0.1252 .5 X (4 +0. 4)(1.25-0- 125)X84 8X100.14.2X9956.5X9.9+56.51. 09X10. 8-0. 8X7. 093. 83X4. 56+3. 83X5. 4413

37、.7X0. 25-3.74-43. 65X4. 7-36.5X0. 375.4X11-5. 410.7X16.1-1.1X10.7 +10.7 X530#第一类：加65+73+135357+288+143272+68+28129+235+171+16517+145+23+35999+99+9+331#6+7+8+102+103+1049998+3+99+998+3+9#第二类：减400-256-44517-53-47284-159-41#258-42-16545-167-145478-47-178#344- (144+37)236- (1力+36)#第三类乘45x4x523 x5x225x9x

38、4#8x (125x13)(250x125) x (4x8)88x12572x125125x64x2542x125x8x5 第四类：乘(12+50) x4025x4x88x125125x (40-4)76x10318x12525x4442x2599x999x7832#第五类乘45x37+37x5528x21+28x7917x23-23x7#46+46x5938x46+64x38167x2+167x3+167x599x32+3239x8+6x39-39x4#99x22+33x34第六类：除360U2504-54-2600-?124-58004-54-84805282404-5-12420W352

39、4004-2578004-12528x225-2x225-6x225(42+25) X125+ (18+15) x!2523x2x4+25x4x2+27x1x8+25x8x1#第七类：加减92+99323+189-123197+102248-86+48354-108672-36+64127-98(6467-832) + (1832-1467)1530+ (592-530) -192(2+4+6+98+100) (1+3+5+97+99)第八类：乘除960x4624899000-121x113702x38*1234640三(164-4)10002 (12544)第九类：加减乘除(98+147)

40、449(230-23) 423(250-25) 4-2533#17364-28+1064-28125x (860+24012)#700+612士12x4(37+15) X85+1360#2005x20062006-2006x20052005#158+262+138375+219+381+2255001-247-1021-232(181+2564) +2719378+44+114+242+222276+228+353+219(375+1034)+(966+125)(2130+783+270)+101799+999+9999+999997755-(2187+755)2214+638+2863065

41、-738-106534#899+3442357183-317-3572365-1086-214497-2992370+19953999+4981883-39812x2575x24138x25x4(13x125)x(3x8)(12+24+80)x50简便计算练习题232x(25+125)88x125704x2525x32x125#102x7658x98178x101-17884x36+64x8475x99+2x7583x102-83x298x199123x18-123x3+85x123#50x(34x4)x325x (24+16)178x99+17879x42+79+79x5773004-254

42、-4810075168001203 01004-2100320004400215004-12549700-7001248W243150W15480025简便计算练习题32356- (1356-721)1235 (1780-1665)75x27+19x2531x870+13x3104x(25x65+25x28)(300+6)x1225x(4+8)125x(35+8)(13+24)x884x101504x2578x10225x20499x6499x16638x99999x9999X13+1325+199X2532X16+14X3278X4+78X3+78X3125X32X8简便计算练习题43600

43、-254810044-7525X32X12530002125888X12572X1251250-255361200-624-762100-728-772273-73-27847-527-273278+463+22+37732+580+2681034+780320+102425+14+18637#214- (86+14)787- (87-29)365- (65+118)455- (155+230)576-285+85825-657+57690-177+77755-287+87100+1-100+148X99+11000+8-1000+85+95X28871-299157-99363-199968

44、-599简便计算练习题5600-60-1520X4-20X4736-35X2025X44-25X498-18X5+2556X8-56X8280-80- 412X6-12X6175-75-2525X8 三 25X880-20X2+6036X9-36X936-366-625X8W (25X8)100+45-100+4515X97+3#102+1-102+165+35X1325+75-25+7540+36020-1013+24X8672-36+64324-68+32100-36+64简便计算练习题626x39+61x26356x9-56x999x55+5578x101-7852x76+47x76+7

45、6134x56134+45x13448x52x2-4x4825x23x (40+4)999x999+1999184+98695+202864-199738-301380+476+120(569+468) + (432+131)704x25256-147-53373-129+29189- (89+74)28x4x25125x32x259x72x12538#简便计算练习题7456- (256-36)102x35 98x42720-164-56304-42158+262+138375+219+381+2255001-247-1021-232(181+2564) +2719#378+44+114+24

46、2+222276+228+353+219(375+1034)+(966+125)(2130+783+270)+101799+999+9999+999997755-(2187+755)2214+638+2863065-738-1065899+34423571833173572365-1086-214497-2992370+1995简便计算练习题83999+498188339812x2575x24138x25x4(13x125)x(3x8)(12+24+80)x5025x32x12532x(25+125)84x36+64x8488x12575x99+2x75102x7698x199178x101-178123x18123x3+85x12350x(34x4)x325x (24+16