简便运算的练习题和答案

1、运算定律练习题(1)乘法交换律：axb=bxa38x25x 442x125x 8乘法结合律：(axb) xc=ax (bxc)25x17x4(25x 125) x ( 8x4)49x4x538x125x8x3(125x25)x45 x289x2(125x12) x8125x (12x4)(2)乘法交换律和结合律的变化练习125x64125x 8844x25125x2425x28(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+7

2、8 + 2258+39+42+61138+293+62+107(4)乘法分配律：(a+b) xc=ax c+bx c正用练习(80+4) x25(20+4) x 25(125+17) x825x (40+4)15x (20+3)(5)乘法分配律正用的变化练习：36 m25 39 m01125 88201x24(6)乘法分配律反用的练习：34x72+34x2835x37 + 65x3785x82+85x 1825x 97+ 25x376x25 + 25x 247)乘法分配律反用的变化练习：38x 29+ 3875x299+7564 x 199+ 6435x68 + 68+68x64思考题：( 8

3、)其他的一些简便运算。800+ 256000+ 1253600+8 + 558x 1015874x99【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 笠5=(325m) + (25 4)=1300t00=13【练一练 1】(1) 450攵5(2) 525攵5(3) 3500+125(4) 10000e25(5) 49500得00(6) 9000攵25【经典例题二】计算25x125x4刈【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。25m25m刈=

4、(25m) x (1258)= 100x1000=100000【练一练 2】(1) 125x15 刈必(2) 25x24(3) 125x16(4) 75x6(5) 1252532(6) 255x64125【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+43m6+43x52+43=125x (34+66)=43x(11+36+52+1)=125x100=125003】计算下面各题：(1) 125 64+125 36=43x100=4300(2) 64x

5、45+64x71-64 x6(3) 21m3+26x21+21【经典例题四】计算(1) (360+108)36(2) 1攵+3 +2+5攵+7攵【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 。利用这一性质，可以使计算简便。(1) (360+108) 36(2) 12+3 攵+5 攵+7 攵=36036+108-36= (1+3+5+7)笠=10+3=16攵=13=8【练一练 4】(1) (720+96)攵4(2) (4500-90) f5(3) 6342攵1(4) 881139(5) 73 36+105-k36+146-36(6) (10000-1000-1

6、00-10)勺0【经典例题五】158 x61h9m【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。158 61 79 3=1587961刈=2x61 3=366【练一练5】计算下面各题：(1) 238m6t195(2) 138x27毋9x50(3) 624x48312-8(4) 40631204203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勺6=103x (96t6)=103x6【经典例题六】计算下面各题:(2) 200+

7、 (25m)(1) 10396t6【思路导航】这两道题都是乘除法混合运算，我们可以根据这两道题的特点，采用加括号和可以概括为：括号前是乘号，力口、去括号不改号，括号前是除(2) 200+ (254)=200攵5m=8x4=618=322)1000 + (125%)6】计算下面各题：(1) 612m66t83(3) (13x8x56) + (45x6)(4) 241 刈45e78345x (678241)【经典例题七】计算：(1) 68x62(2) 85刈5【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，并把积直接写在末尾，如果积不满10，十位上要补写0，

8、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) 68 62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) 23 27(2) 46 m4(3) 55 x55(4) 91 99【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 作积的头，第二步6 作积的尾，第三步2+6=8

9、 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。358 11,第一步用3作积的头，第二步用8作积的尾，在用35+58=93,合起来是3938。【练一练 9计算(1) 353x11(2) 654x11(3) 896x11【练一练1】(1) 450攵5(2) 525攵5(3) 3500+125(4) 10000毋25(5) 49500用00(6) 9000225【练一练2】(1

10、) 125x15刈必(2) 25 24(3) 125 x16(4) 75x16(5) 125 25 32(6) 25x564m25(2) 64 45+64x71-64 x6(3) 21 73+2621+21【练一练3】计算下面各题:(1) 12564+12536【练一练 4】(1) (720+96)攵4(2) (4500-90) m5(3) 6342攵1(4) 881139(5)73 36+105 36+146 36(6) (10000-1000-100-10)勺0(2) 138 27 令9 50【练一练5】计算下面各题:(1) 238m6t195(3) 624x483123(4) 406x3

11、12勺04攵03【练一练6】计算下面各题:(2) 1000+ ( 1253)(1) 612m66t83(3) (13856) + (456)(4) 241m45令78345x (678笠41)【练一练7】（1） 23 x27(2) 46 m4(3) 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) 896m1158+262+138简便计算专题训练375+219+381+2255001 -247-1021 -232276+228+353+219(181+2564) +

12、2719378+44+114+242+222(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 -39812x2575x24138 x25 44(13 m25) (3 8)(12+24+80) x50简便计算练习题2704 x2525 x32 x12532x(25+125)88x125102x7658x98178x101 -

13、17884x36+64x8475x99+2x7583 x102 83 x298 x199123x18-123x3+85x12350 x(34 m) )325x (24+16)178x99+17879 2+79+79x5773002548100+47516800+1203010021003200040021500+12549700+7001248+243150+154800 攵5简便计算练习题32356 (1356721 )1235 ( 1780 1665)75x27+19x2 531x870+13x3104x(25 65+25x28)(300+6)x1225x(4+8)125x(35+8)84

14、x101504x2578x10299x6499x16638x9999x13+1325+199x2532x16+14x32125x32x825x32x12588x1253600 254简便计算练习题48100 fh53000-12581200-624-762100-728-772273-73-27(13+24)x825x204999x9978x4+78x3+78x372x1251250+25 w847-527-273278+463+22+37732+580+2681034+780320+102425+14+186214- (86+14)787- (87-29)365- (65+118)455-

15、(155+230 )576-285+85825-657+57690-177+77755-287+87871-299157-99363-199968-599178x101-17883x102-83x217x23-23x735x127-35x16-11x3525x4+25x412x6 12x6简便计算练习题5容易出错类型（共五种类型）600-60 1520x4 20x4+736-35x2098-18x5+2556x856x8 +280-80 -4175-75 笠536-36 h-6100+1-100+136x936x915x97+35+95x2825x8 25x8 +25x8(25x8 尸48x9

16、9+180-20x2+60100+45-100+451000+8-1000+8102+1-102+165+35x1325+75-25+7540+360-20-1013+24x8672-36+64324-68+32100-36+6426x 39+61x2678x101- 7848x52x2-4x48184+98695380 + 476+ 120256-147-5328x4x25简便计算练习题6356x 9-56x 999x 55+5552x76+ 47x7 6+ 7625x 23x (40+4)+ 202864-199(569+468) + ( 432+131)373 129+29125x 32

17、x25189134x 56- 134+45x 134999x 999+ 1999738 301704x 25(89 + 74)9x72x125720+ 16+5简便计算练习题7630- 42456(256 36)102x 35 98 x42158+262+138375+219+381+2255001 247 1021-232(181+2564) +2719378+44+114+242+22299+999+9999+99999276+228+353+219(375+1034)+(966+125)(2130+783+270)+10177755-(2187+755)2214+638+2863065-

18、738-1065899+3442357-183-317-3572365- 1086-214497-2992370+19953999+498简便计算练习题81883-39812x2575x24138x 25x 4(13x125)x(3 x8)(12+24+80) x 5025x 32x 12532x(25+125)88x125102x 76178x 101 17884 x 36+64x 8475 x 99+2x 7598x199123x 18-123x 3+85x 12350x(34x4) x325x (24+16)178x99+17879x42+79+79x577300+ 25+48100+

19、4+75158+262+1381248+ 24简便计算练习题93150 154800+ 2521500+ 125375+219+381+225 5001 -247- 1021-232(181+2564) +2719378+44+114+242+222 276+228+353+219 (375+1034)+(966+125)(2130+783+270)+1017 99+999+9999+99999 7755-(2187+755)2214+638+2863065-738- 1065899+3442357- 183-317-3572365-1086-214497-2992370+19953999+4

20、981883-39812x25简便计算练习题1075 x 24138x 25x 4(13x125)x(3x8)(12+24+80) x 50704x 2525x32x12532 (25+125)88 125102 7658 98178x101- 17884 36+64 8475 99+2 7583x 102 83x298 199123x18-123x3+85x12350 (34 4) 325x (24+16)178 99+17879 42+79+79 5721500+ 12516800+ 1207300+ 25+48100+ 4+ 75简便计算练习题11(a+b) + c = a + ( b+

21、c)a b c = a (b+c)100.4322.5689.35.26 2.7414.9 (5.2 +4.9 )18.32 5.47 4.32(a x b ) x c = a25 x 6.8 x 0.04x (b x c )6.4 x 1.25 x 12.50.25 x 32 x 0.125c x ( a+b) = c x a + cxb0.452010.58 x 10.150.2994.79.9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 + 2.3 x 9.90.18+4.26 -0.18 +4.260.58 x1.3 +

22、0.58 x1.37.3 +4 + 2.7 x 0.255.26 x 0.125 + 2.74 + 8义 8)12.8 + (0.4 义 1.6 )3.75 x 0.5 a + b + c = a 6.3 + 1.82.75 + 2一 (b x c)9.5 + (1.9930 + 0.6 +563.4 + 2.5 + 0.4(7.7 + 1.54 ) + 0.7简便计算练习题136.9 +4.8 +3.115.89+(6.75 5.89) 7.85+2.34 0.85 +4.6635.6 1.8 15.6 7.2 13.75 (3.75 + 6.48) 47.8 7.45+2.5566.86

23、-8.66 -1.340.25 x16.2 x40.25 x 32 x 0.1252 .5 x(4 +0.4)(1.250.125)x84.8 x 100.14.2 义 9956.5 义 9.9 + 56.57.09 x 10.8 0.8 义 7.093.83 义 4.56 + 3.83 义 5.443.65 义 4.7 36.5 义 0.375.4 x 11 -5.413.7 x0.25-3.7-410.7 x 16.1 -1.1 x10.7 +10.7 x5简便计算专题训练158+262+138375+219+381+2255001 -247-1021 -232(181+2564 ) +2

24、719378+44+114+242+222276+228+353+219(375+1034)+(966+125)(2130+783+270)+101799+999+9999+999997755 -(2187+755)2214+638+2863065 738 -899+3442357-183-317-3572365 1086 497 2992370+19953999+4981883 -39812x2575x24138 x25 w(13 m25) x3 8)(12+24+80) x50704 x25简便计算练习题225 x32 x12532 x(25+125)88x125102x7658x9810

25、65214178x101 -17884x36+64x8475x99+2x7583 x102 83 x298 x199123x18 123x3+85x12350 x(34 m) )325x (24+16)178x99+17879 2+79+79x577300-25 w8100fh516800+1203010021003200040021500+125497007001248+243150154800 攵5简便计算练习题32356 (1356-721 )1235- (1780- 1665)75x27+19x2 531 x870+13x3104x(25 65+25x28)(300+6)x1225x(

26、4+8)125x(35+8)(13+24)x884x101504x2578x10225x20499x6499x16638x99999x9999x13+1325+199x2532x16+14x3278x4+78x3+78x3125x32x825x32x12588x12572x1253600 254简便计算练习题48100 fh53000-12581250+25 w1200-624-762100-728-772273-73-27847-527-273278+463+22+37732+580+2681034+780320+102425+14+186214- (86+14)787- (87-29)36

27、5- (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（共五种类型）600-60 1520x420x4+736-35x2025x4+25x498-18x5+2556x856x8+280-80 -412x6 12x6175-75 2525x825x8 +80-20x2+6036x936x936-36 6-625x8(25x8 )-100+

28、45-100+4515x97+3100+1-100+148x99+11000+8-1000+85+95x28102+1-102+165+35x1325+75-25+7540+360-20-1013+24x8672-36+64324-68+32100-36+6426x 39+61x26简便计算练习题6356x9 56x999x55+ 5578x101- 7852x76+47x76+ 76134x56 134 + 45x 13448x52x2-4x4825x23x (40 + 4)999x999+ 1999184+98695+202864-199738-301380 + 476+ 120(569+

29、468) + ( 432+ 131)256-147-53373129+29189704x 25(89+74)28x4x25125x 32x259x72x125720+ 16+5简便计算练习题7630- 42456(25636)102x35 98 x42158+262+138375+219+381+2255001 -247-1021-232(181+2564) +2719378+44+114+242+222(2130+783+270)+10173065-738-1065899+3442357-183-317-357276+228+353+219(375+1034)+(966+125)99+999

30、+9999+999997755-(2187+755)2214+638+2862365- 1086-214497-2992370+1995简便计算练习题83999+4981883-39812x2575 x 24138x 25x 4(13x125)x(3x8)(12+24+80) x 5025x 32x 12532x(25+125)88x125102x 76178x101- 17884x36+64x 8475x99+2x 7598x199123x18-123x3+85x12350x(34x4) x 379x42+79+79x5725x (24+16)178x99+17888x125102x7658

31、x98178x101- 1787300+ 25+48100+4+75158+262+138简便计算练习题91248243150154800+2521500+ 125375+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+344497-2992357- 183-317-3572365- 108

32、6-2142370+19953999+4981883-39812x25(13x125)x(3x8)简便计算练习题1075x24138x 25x4(12+24+80) x50704x 2525x32x12532x(25+125)84x36+64x 8475x99+2x 7583 x 102-83x298x199123x 18-123x3+85x 12350x(34x4) x325x ( 24+16)178x99+17879x42+79+79x5721500-1257300-25-48100-4-75简便计算练习题16800-12011(a+b) + c = a2.73 + 0.89 + ( b+

33、c)1.274.37+ 0.28 +1.63+ 5.72a b c = a(b+c)10 - 0.432 - 2.5689.3-5.26 - 2.7414.9 - (5.2 +4.9 )18.32-5.47 - 4.32(a x b ) x c = a25 x 6.8 x 0.04(b x0.25 x 32 x 0.1256.41.25 x 12.5c x ( a+b) = c x a 0.45 x 201ex b0.58 x 10.150.2 x 994.7 x 9.92.1 x 99 + 2.1简便计算练习题123.28 x 5.7 + 6.72 x 5.723 x 0.1 + 2.3 x

34、 9.90.18+ 4.26 -0.18 +4.260.58 x1.3 + 0.58 x1.37.3 +4 + 2.7 x 0.253.75 x 0.5 2.75 + 25.26 x 0.125 + 2.74 + 8a + b + c = a6.3 + 1.8一 (b x c)9.5 + (1.9 x 8)12.8 + (0.4 义 1.6 )930 + 0.6 +563.4 + 2.5 + 0.4(7.7 + 1.54 ) + 0.7+ 2.34 -0.85 + 4.66简便计算练习题136.9 +4.8 +3.115.89+(6.75 5.89)7.85-7.45+2.5535.6 1.8

35、 15.6 7.213.75 (3.75 + 6.48)47.866.86 -8.66 -1.340.25x16.2x40.25 x32 x 0.1252 .5 x (4 +0.4)(1.25-0.125) x84.8 x 100.188x12572x25125 64 253.83 x 4.56+3.83 x 5.443.65 x 4.736.5 x 0.375.4 x 11-5.413.7 x0.25-3.7-410.7 x16.1 -1.1 x10.7 +10.7第一类：加65+73+135357+288+143272+68+28129+235+171+16517+145+23+35999

36、+99+9+3517-53-47284-159-416+7+8+102+103+104第二类：减400-256-449998+3+99+998+3+9258-42-16545-167-145478-47-178344- (144+37)236- (177+36)第三类：乘45 4 523 5 225 9 48x (125x3)(250m25) x (4x8)42x125 8 525x4m8m25第四类：乘18 125(12+50) 40125 x (40-4)76x10325x4442x2599 999 78第五类：乘45 37+37 5528 21+28 7917 23-23 738 46+

37、64 3899 32+3246+46 59167 2+167 3+167 539 8+6 39-39 428 225-2 225-6 225(42+25) m25+ (18+15) x12523 2 4+25 4 2+27 1 8+25 8 199 22+33 34第六类：除360% 得250 芍攵600t2 芍800 七 3480 h5 f8240芍 t2420352400257800 t25第七类：加减92+99197+102354-108127-98323+189-123248-86+48672-36+64(6467-832) + (1832-1467)1530+ (592-530) -

38、192(2+4+6+98+100) - (1+3+5+97+99)第八类：乘除960m6m899000t21 x13702 m8 t234640 + ( 16m)1000+ (125m)第九类：加减乘除(98+147) f9(230-23)笠3(250-25)笠51736 28+1064 28125 x (860+240 t2)700+612 t2 m(37+15) 85+13602005 20062006-2006 20052005158+262+138375+219+381+2255001 247 1021- 232(181+2564) +2719378+44+114+242+222276

39、+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 398122575 24138 25 4(13 125) (3 8)(12+24+80)50简便计算练习题704 2525 32 12532 (25+125)88 125102 7658 98178x101-17884 36+64 8475 99+2

40、 7583x102-83 298 199123m8123 刈+85x12350 (34 4) 325x(24+16)178 99+17879 42+79+79 57730025 m8100m 516800 t2030100 210032000 m0021500 t2549700勺001248243150 15 480025简便计算练习题 32356(1356 721)1235( 1780 1665)7527+19x2 5(300+6)x1225x(4+8)78x4+78x3+78x3简便计算练习题 4360025 m125x32x88100m 525x32x1253000 t25 31200-

41、624-762100-728-772273-73-2788x12572x1251250笠5芍847-527-27331 870+13 3104x25 )65+25 28)125x(35+8)(13+24)x884x101504x2578x10225x20499x6499x16638x9932x16+14x32999x9999x13+1325+199x25278+463+22+37732+580+2681034+780320+102425+14+186214-（ 86+14）787-（ 87-29）365-（ 65+118）455-（ 155+230）576-285+85825-657+5769

42、0-177+77755-287+87871-299157-99363-199968-599600-60 1520x4 攵0x4736-35x2025x4+25x498-18x5+2556x8 y6x8280-80 -412x6 +12x6175-75 2525x8+25x880-20x2+6036x9+36x936-36 6-625x8+ （25x8）100+45-100+4515x97+3100+1-100+148x99+11000+8-1000+85+95x28简便计算练习题 5102+1-102+165+35x1325+75-25+7540+36020-1013+24x8672-36+6

43、4324-68+32100-36+64简便计算练习题626 m9+ 61 26356 9-56 999x55+5578x101-7852x76+ 47 76+76134 56-134+45x13448 52x24x4825x23x (40+4)999 999+ 1999184+ 98695+ 202864-199738-301380+476+120(569+ 468) + ( 432+ 131)704 25256-147-53373 129+29189 (89+74)28x4 25125 32 259m2x25简便计算练习题7720t6芍630 m2456 (256 36)102 m5 98 42158+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- 7381065899+3442357 183 317 3572365 1086 214497