题目内容
(1)438+203 | (2)256+199 | (3)416-302 | (4)325-198 |
(5)278+498 | (6)3.6+2.7+6.4+7.3 | (7)+++ | (8)1.3+4.25+3.7+3 |
(9)1874-324-476 | (10)5-1.4-1.6 | (11)30-8.12-4.13-7.75 | (12)-+ |
(13)4.3-2.45+5.7-6.55 | (14)125×48 | (15)25×32 | (16)35×1.4 |
(17)1.25×88 | (18)0.25×444 | (19)32×0.25×12.5 | (20)25×80×0.04×125 |
(21)1.9×4×0.5 | (22)25×1.25×4×0.8 | (23)(1.6+1.6+1.6+1.6)×2.5 | (24)(0.7+0.7…+0.7)×12.5(80个0.7相加) |
(24)9.9×8.6+8.6 | (25)99×5.4 | ||
(26)4.8×1.01 | (27)95×101-95 | (28)95×102-190 | (29)95.6×18+0.4×18 |
(30)(-+)×12 | (31)(+-)÷ | (32)24×(+-) | (33)24÷(+-) |
(34)1.25×3.6+1.25×+ | (35)3.3×+0.75×+75% | (36)×6.6+7.5× | (37)9.56×180-95.6×8 |
(38)4.8×37+47×6.3 | (39)9.5×8.8+0.12×95 | (40)×21 | (41)×33 |
(42)÷ | (43)÷ | (44)÷42 | (45)6×0.75+5×-3÷4 |
(46)5.4÷1.2÷5 | (47)270÷18 | (48)120÷(1.2×4) | (49)73÷0.8÷12.5 |
(50)16÷2.5 | (51)48÷1.25 | (52)-(-)+ | (53)84-(54-16) |
(54)84-(54+16) | (55)9999×7778+3333×6666 | (56)3.6×31.4+43.9×6.4 | (57)(+)× |
(58)×+÷ | (59)-- | (60)×-× | (61)×÷× |
(62)-×- | (63)×[÷(+)] | (64)(0.9+5)×3+2.3 | (65)56× |
(66)+÷+ | (67)(+)÷(+) | (68)÷(-) | (69)(-)÷ |
(70)7.2÷(5-0.75-0.25) | (71)6.4+3.6÷0.5+4.5 | (72)(6.4+3.6)÷0.5+4.5 | (73)495÷55+495÷45 |
(74)8÷0.4+8÷1.6 | (75)0.9+99×0.9 | (76)5.28-(1.62+2.28) | (77)-+ |
(78)4×(+) | (79)+++ | (80)2-(+)- | (81)×+× |
(82)×+× | (83)×9+ | (84)(5+)× | (85)(+)×24 |
(86)(20+)× | (87)×39× | (88)×(+) | (89)(-)×12 |
(90)×(26×) | (91)+++ | (92)17×- | (93)(+)× |
(94)(+)÷ | (95)(+)÷3 | (96)(-)÷ | (97)÷+÷ |
(98)×(10+) | (99)(21+)÷ | (100)×+× | (101)÷+÷ |
(102)(-)÷ | (103)×++ | (104)_×- | (105)-(÷+) |
(106)+×+ | (107)1-÷- | (108)×+÷4 | (109)5-(4+) |
(110)1125-997 | (111)7.46-0.83-2.17 | (112)12.85-1.17-8.83+1.15 | (113)4.5×102 |
(114)0.4×6.3×25 | (115)(4.9+4.9+…+4.9)×2.5(16个4.9相加) | (116)7.5×199 | (117)(+)×36 |
(118)1.2×5.7-1.2+5.3×1.2 | (119)0.825×102-82.5 | (120)46× | (121)560÷16÷5 |
(122)3÷2.5 | (123)84+(54-16) | (124)+++ | (125)-(÷+) |
(126)3×(+)+ | (127)7.2÷(5-0.75+0.25) | (128)725÷25+275÷25 | (129)×× |
(130)×45-÷ | (131)48×(-) | (132)×+× | (133)(32+)÷4 |
(134)÷÷ | (135)46× | (136)×+÷9 |
解:(1)438+203,
=438+200+3,
=641;
(2)256+199,
=256+200-1,
=455;
(3)416-302,
=416-300-2,
=114;
(4)325-198,
=325-200+2,
=127;
(5)278+498,
=278+500-2,
=776;
(6)3.6+2.7+6.4+7.3,
=(3.6+6.4)+(2.7+7.3),
=10+10,
=20;
(7)+++
=()+(),
=1+3,
=4;
(8)1.3+4.25+3.7+3,
=(1.3+3.7)+(4.25+3),
=5+7.25,
=12.25;
(9)1874-324-476,
=1874-(324+476),
=1874-800,
=1074;
(10)5-1.4-1.6
=5-(1.4+1.6),
=5-3,
=2;
(11)30-8.12-4.13-7.75
=30-(8.12+4.13+7.75),
=30-20,
=10;
(11)-+
=+-,
=1-,
=;
(12)4.3-2.45+5.7-6.55
=(4.3+5.7)-(2.45+6.55),
=10-9,
=1;
(13)125×48
=125×8×6,
=1000×6,
=6000;
(14)25×32
=25×4×8,
=100×8,
=800;
(15)35×1.4
=35×0.2×7,
=7×7,
=49;
(16)1.25×88
=1.25×(80+8),
=1.25×80+1.25×8,
=100+10,
=110;
(17)0.25×444
=0.25×4×111,
=111;
(18)32×0.25×12.5
=8×4×0.25×12.5,
=(8×12.5)×(4×0.25),
=100×1,
=100;
(19)25×80×0.04×125
=(125×80)×(25×0.04),
=10000×1,
=10000;
(20)1.9×4×0.5
=1.9×(4×0.5),
=1.9×2,
=3.8
(21)25×1.25×4×0.8
=(25×4)×(1.25×0.8),
=100×1,
=100;
(22)(1.6+1.6+1.6+1.6)×2.5
=1.6×(4×2.5),
=1.6×10,
=16;
(23)(0.7+0.7…+0.7)×12.5(80个0.7相加)
=80×0.7×12.5,
=80×12.5×0.7,
=1000×0.7,
=700;
(24)99×8.6+8.6
=(99+1)×8.6,
=100×8.6,
=860;
(25)99×5.4
=(100-1)×5.4,
=100×5.4-1×5.4,
=540-5.4,
=534.6;
(26)4.8×1.01
=4.8×(1+0.01),
=4.8×1+4.8×0.01,
=4.8+0.048,
=4.848;
(27)95×101-95
=95×(101-1),
=95×100,
=9500;
(28)95×102-190
=95×(100+2)-190,
=95×100+95×2-190,
=9500+190-190,
=9500;
(29)95.6×18+0.4×18
=18×(95.6+0.4),
=18×96,
=18×(100-4),
=18×100-18×4,
=1800-72,
=1728;
(30)(-+)×12
=×12×12×,
=4-2+3,
=5;
(31)(+-)÷
=×24×24×24,
=8+3-1,
=10;
(32)24×(+-)
=×24×24×24,
=8+3-1,
=10;
(33)24÷(+-)
=24,
=24×,
=57.;
(34)1.25×3.6+1.25×+
=1.25×(3.6+3.4+1),
=1.25×8,
=10;
(35)3.3×+0.75×+75%
=0.75×(3.3+5.7+1),
=0.75×10,
=7.5;
(36)×6.6+7.5×
=6.6×(2.5+7.5),
=6.6×10,
=66;
(37)9.56×180-95.6×8
=9.56×180-9.56×80,
=9.56×(180-80),
=9.56×100,
=956;
(38)4.8×37+48×6.3
=48×3.7+48×6.3,
=48×(3.7+6.3),
=48×10,
=480;
(39)9.5×8.8+0.12×95
=(8.8+1.2)×9.5,
=10×9.5,
=950;
(40)×21
=×(20+1),
=×20+×1,
=19;
(41)×33
=×(30+3),
=×30+×3,
=7+,
=7;
(42)÷,
=
=;
(43)÷
=×48,
=;
(44)÷42,
=×,
=;
(45)6×0.75+5×-3÷4
=(6+5-1)×0.75,
=10×0.75,
=7.5;
(46)5.4÷1.2÷5
=5.4÷(1.2×5),
=5.4÷6,
=0.9;
(47)270÷18,
=15;
(48)120÷(1.2×4)
=120÷1.2÷4,
=100÷4,
=25;
(49)73÷0.8÷12.5
=73÷(0.8×12.5),
=73÷10,
=7.3;
(50)16÷2.5
=16÷(2.5×4)×4,
=16÷10×4,
=6.4;
(51)48÷1.25
=48÷(1.25×8)×8,
=48÷10×8,
=38.4;
(52)-(-)+
=-++,
=;
(53)84-(54-16)
=84-54+16,
=46;
(54)84-(54+16)
=84-70,
=14;
(55)9999×7778+3333×6666
=9999×7778+3333×3×2222,
=9999×7778+9999×2222,
=9999×(7778+2222),
=9999×10000,
=99990000;
(56)3.6×31.4+43.9×6.4
=3.6×(43.9-12.5)+43.9×6.4,
=439-3.6×12.5,
=439-45,
=394;
(57)(+)×
=×+×,
=+2,
=5;
(58)×+÷
=()×,
=;
(59)--
=-(+),
=-1,
=;
(60)×-×
=×(),
=×,
=;
(61)×÷×
=÷×,
=;
(62)-×-
=-,
=-(),
=-1,
=;
(63)×[÷(+)]
=×[×+×7],
=×(+3),
=××3,
=,
=;
(64)(0.9+5)×3+2.3
=5.9×3+2.3,
=17.7+2.3,
=20;
(65)56×=;
(66)+÷+
=+,
=1;
(67)(+)÷(+)
=1÷1,
=1;
(68)÷(-)
=×,
=;
(69)(-)÷
=×-×,
=-,
=;
(70)7.2÷(5-0.75-0.25)
=7.2÷[5-(0.75+0.25)],
=7.2÷(5-1),
=7.2÷4,
=1.8;
(71)6.4+3.6÷0.5+4.5
=6.4+7.2+4.5,
=18.1;
(72)(6.4+3.6)÷0.5+4.5
=10÷0.5+4.5,
=20+4.5,
=24.5;
(73)495÷55+495÷45
=9+11,
=20;
(74)8÷0.4+8÷1.6
=20+5,
=25;
(75)0.9+99×0.9
=0.9×(1+99),
=0.9×100,
=90;
(76)5.28-(1.62+2.28)
=5.28-2.28-1.62,
=3-1.62,
=1.38;
(77)-+
=0+,
=;
(78)4×(+)
=4×+4×,
=,
=;
(79)+++
=()+(),
=1+1,
=2;
(88)×(+)
=××,
=1+,
=1;
(89)(-)×12
=×12×12,
=3-2,
=1;
(90)×(26×)
=××26,
=6;
(91)+++
=()+(),
=1+1,
=2;
(92)17×-
=(17-1)×,
=16×,
=6;
(93)(+)×
=××,
=1+,
=;
(94)(+)÷
=×+×,
=+1,
=1;
(95)(+)÷3
=××,
=,
=;
(96)(-)÷
=×9-×9,
=,
=;
(97)÷+÷
=()×,
=;
(98)×(10+)
=×10+×,
=8,
=8;
(99)(21+)÷
=21×+×,
=15+,
=15;
(100)×+×
=()×,
=1×,
=;
(101)÷+÷
=()×,
=4×,
=17;
(102)(-)÷
=×-,
=,
=;
(103)×+
=,
=;
(104)-×-
=-,
=-(),
=-1,
=;
(105)-(÷+)
=--,
=1-,
=;
(106)+×+
=+(),
=+1,
=1;
(107)1-÷-
=1-(),
=1-1,
=0;
(108)×+÷4
=()×,
=1×,
=;
(109)5-(4+)
=5-4-,
=1-,
=;
(110)1125-997
=1125-1000+3,
=125+3,
=128;
(111)7.46-0.83-2.17
=7.46-(0.83+2.17),
=7.46-3,
=4.46;
(112)12.85-1.17-8.83+1.15
=(12.85+1.15)-(1.17+8.83),
=14-10,
=4;
(113)4.5×102
=4.5×(100+2),
=4.5×100+4.5×2,
=450+9,
=459;
(114)0.4×6.3×25
=0.4×25×6.3,
=10×6.3,
=63;
(115)(4.9+4.9+…+4.9)×2.5(16个4.9相加)
=4.9×16×2.5,
=4.9×(4×2.5×4),
=4.9×40,
=196;
(116)7.5×199
=7.5×(200-1),
=7.5×200-7.5×1,
=1500-7.5,
=1492.5;
(117)(+)×36
=×36,
=4+3,
=7;
(118)1.2×5.7-1.2+5.3×1.2
=(5.7+5.3-1)×1.2,
=10×1.2,
=12;
(119)0.825×102-82.5
=0.825×102-0.825×100,
=0.825×(102-100),
=0.825×2,
=1.65;
(120)46×=;
(121)560÷16÷5
=560÷(16×5),
=560÷80,
=7;
(122)3÷2.5,
=1.2;
(123)84+(54-16)
=84+38,
=122;
(124)+++
=(+)+(+),
=1+1,
=2;
(125)-(÷+)
=--,
=1-,
=;
(126)3×(+)+
=3×,
=(),
=1+,
=1;
(127)7.2÷(5-0.75+0.25)
=7.2÷4.5,
=1.6;
(128)725÷25+275÷25
=(725+275)÷25,
=1000÷25,
=40;
(129)××
=××,
=,
=;
(130)×45-÷
=×45-×45,
=0;
(131)48×(-)
=48×,
=40-18,
=22;
(132)×+×
=,
=;
(133)(32+)÷4
=32×,
=8+,
=8;
(134)÷÷
=,
=1;
(135)46×,
=(45+1)×,
=45×+;
=2;
(136)×+÷9
=()×,
=1×,
=.
分析:本题按照先算乘除再算加减,有括号的先算括号里面的顺序运算.注意观察算式的特点,能运用运算定律简算,或者其它简便方法简算的要简算.
点评:本题是考察的基本运算法则,根据运算顺序计算.本题有很多可以简算,用相关的运算定律简算.
=438+200+3,
=641;
(2)256+199,
=256+200-1,
=455;
(3)416-302,
=416-300-2,
=114;
(4)325-198,
=325-200+2,
=127;
(5)278+498,
=278+500-2,
=776;
(6)3.6+2.7+6.4+7.3,
=(3.6+6.4)+(2.7+7.3),
=10+10,
=20;
(7)+++
=()+(),
=1+3,
=4;
(8)1.3+4.25+3.7+3,
=(1.3+3.7)+(4.25+3),
=5+7.25,
=12.25;
(9)1874-324-476,
=1874-(324+476),
=1874-800,
=1074;
(10)5-1.4-1.6
=5-(1.4+1.6),
=5-3,
=2;
(11)30-8.12-4.13-7.75
=30-(8.12+4.13+7.75),
=30-20,
=10;
(11)-+
=+-,
=1-,
=;
(12)4.3-2.45+5.7-6.55
=(4.3+5.7)-(2.45+6.55),
=10-9,
=1;
(13)125×48
=125×8×6,
=1000×6,
=6000;
(14)25×32
=25×4×8,
=100×8,
=800;
(15)35×1.4
=35×0.2×7,
=7×7,
=49;
(16)1.25×88
=1.25×(80+8),
=1.25×80+1.25×8,
=100+10,
=110;
(17)0.25×444
=0.25×4×111,
=111;
(18)32×0.25×12.5
=8×4×0.25×12.5,
=(8×12.5)×(4×0.25),
=100×1,
=100;
(19)25×80×0.04×125
=(125×80)×(25×0.04),
=10000×1,
=10000;
(20)1.9×4×0.5
=1.9×(4×0.5),
=1.9×2,
=3.8
(21)25×1.25×4×0.8
=(25×4)×(1.25×0.8),
=100×1,
=100;
(22)(1.6+1.6+1.6+1.6)×2.5
=1.6×(4×2.5),
=1.6×10,
=16;
(23)(0.7+0.7…+0.7)×12.5(80个0.7相加)
=80×0.7×12.5,
=80×12.5×0.7,
=1000×0.7,
=700;
(24)99×8.6+8.6
=(99+1)×8.6,
=100×8.6,
=860;
(25)99×5.4
=(100-1)×5.4,
=100×5.4-1×5.4,
=540-5.4,
=534.6;
(26)4.8×1.01
=4.8×(1+0.01),
=4.8×1+4.8×0.01,
=4.8+0.048,
=4.848;
(27)95×101-95
=95×(101-1),
=95×100,
=9500;
(28)95×102-190
=95×(100+2)-190,
=95×100+95×2-190,
=9500+190-190,
=9500;
(29)95.6×18+0.4×18
=18×(95.6+0.4),
=18×96,
=18×(100-4),
=18×100-18×4,
=1800-72,
=1728;
(30)(-+)×12
=×12×12×,
=4-2+3,
=5;
(31)(+-)÷
=×24×24×24,
=8+3-1,
=10;
(32)24×(+-)
=×24×24×24,
=8+3-1,
=10;
(33)24÷(+-)
=24,
=24×,
=57.;
(34)1.25×3.6+1.25×+
=1.25×(3.6+3.4+1),
=1.25×8,
=10;
(35)3.3×+0.75×+75%
=0.75×(3.3+5.7+1),
=0.75×10,
=7.5;
(36)×6.6+7.5×
=6.6×(2.5+7.5),
=6.6×10,
=66;
(37)9.56×180-95.6×8
=9.56×180-9.56×80,
=9.56×(180-80),
=9.56×100,
=956;
(38)4.8×37+48×6.3
=48×3.7+48×6.3,
=48×(3.7+6.3),
=48×10,
=480;
(39)9.5×8.8+0.12×95
=(8.8+1.2)×9.5,
=10×9.5,
=950;
(40)×21
=×(20+1),
=×20+×1,
=19;
(41)×33
=×(30+3),
=×30+×3,
=7+,
=7;
(42)÷,
=
=;
(43)÷
=×48,
=;
(44)÷42,
=×,
=;
(45)6×0.75+5×-3÷4
=(6+5-1)×0.75,
=10×0.75,
=7.5;
(46)5.4÷1.2÷5
=5.4÷(1.2×5),
=5.4÷6,
=0.9;
(47)270÷18,
=15;
(48)120÷(1.2×4)
=120÷1.2÷4,
=100÷4,
=25;
(49)73÷0.8÷12.5
=73÷(0.8×12.5),
=73÷10,
=7.3;
(50)16÷2.5
=16÷(2.5×4)×4,
=16÷10×4,
=6.4;
(51)48÷1.25
=48÷(1.25×8)×8,
=48÷10×8,
=38.4;
(52)-(-)+
=-++,
=;
(53)84-(54-16)
=84-54+16,
=46;
(54)84-(54+16)
=84-70,
=14;
(55)9999×7778+3333×6666
=9999×7778+3333×3×2222,
=9999×7778+9999×2222,
=9999×(7778+2222),
=9999×10000,
=99990000;
(56)3.6×31.4+43.9×6.4
=3.6×(43.9-12.5)+43.9×6.4,
=439-3.6×12.5,
=439-45,
=394;
(57)(+)×
=×+×,
=+2,
=5;
(58)×+÷
=()×,
=;
(59)--
=-(+),
=-1,
=;
(60)×-×
=×(),
=×,
=;
(61)×÷×
=÷×,
=;
(62)-×-
=-,
=-(),
=-1,
=;
(63)×[÷(+)]
=×[×+×7],
=×(+3),
=××3,
=,
=;
(64)(0.9+5)×3+2.3
=5.9×3+2.3,
=17.7+2.3,
=20;
(65)56×=;
(66)+÷+
=+,
=1;
(67)(+)÷(+)
=1÷1,
=1;
(68)÷(-)
=×,
=;
(69)(-)÷
=×-×,
=-,
=;
(70)7.2÷(5-0.75-0.25)
=7.2÷[5-(0.75+0.25)],
=7.2÷(5-1),
=7.2÷4,
=1.8;
(71)6.4+3.6÷0.5+4.5
=6.4+7.2+4.5,
=18.1;
(72)(6.4+3.6)÷0.5+4.5
=10÷0.5+4.5,
=20+4.5,
=24.5;
(73)495÷55+495÷45
=9+11,
=20;
(74)8÷0.4+8÷1.6
=20+5,
=25;
(75)0.9+99×0.9
=0.9×(1+99),
=0.9×100,
=90;
(76)5.28-(1.62+2.28)
=5.28-2.28-1.62,
=3-1.62,
=1.38;
(77)-+
=0+,
=;
(78)4×(+)
=4×+4×,
=,
=;
(79)+++
=()+(),
=1+1,
=2;
(80)2-(+)- =2-, =2-(), =2-1, =1; (81)×+× =()×, =1×, =; (82)×+× =()×, =1×, =; (83)×9+ =(9+1)×, =; (84)(20+)× =20×+×, =14+, =14; (85)(5+)× =5×+×, =4+, =4; (86)(+)×24 =×24+×24, =4+3, =7; (87)×39× =3×, =; |
=××,
=1+,
=1;
(89)(-)×12
=×12×12,
=3-2,
=1;
(90)×(26×)
=××26,
=6;
(91)+++
=()+(),
=1+1,
=2;
(92)17×-
=(17-1)×,
=16×,
=6;
(93)(+)×
=××,
=1+,
=;
(94)(+)÷
=×+×,
=+1,
=1;
(95)(+)÷3
=××,
=,
=;
(96)(-)÷
=×9-×9,
=,
=;
(97)÷+÷
=()×,
=;
(98)×(10+)
=×10+×,
=8,
=8;
(99)(21+)÷
=21×+×,
=15+,
=15;
(100)×+×
=()×,
=1×,
=;
(101)÷+÷
=()×,
=4×,
=17;
(102)(-)÷
=×-,
=,
=;
(103)×+
=,
=;
(104)-×-
=-,
=-(),
=-1,
=;
(105)-(÷+)
=--,
=1-,
=;
(106)+×+
=+(),
=+1,
=1;
(107)1-÷-
=1-(),
=1-1,
=0;
(108)×+÷4
=()×,
=1×,
=;
(109)5-(4+)
=5-4-,
=1-,
=;
(110)1125-997
=1125-1000+3,
=125+3,
=128;
(111)7.46-0.83-2.17
=7.46-(0.83+2.17),
=7.46-3,
=4.46;
(112)12.85-1.17-8.83+1.15
=(12.85+1.15)-(1.17+8.83),
=14-10,
=4;
(113)4.5×102
=4.5×(100+2),
=4.5×100+4.5×2,
=450+9,
=459;
(114)0.4×6.3×25
=0.4×25×6.3,
=10×6.3,
=63;
(115)(4.9+4.9+…+4.9)×2.5(16个4.9相加)
=4.9×16×2.5,
=4.9×(4×2.5×4),
=4.9×40,
=196;
(116)7.5×199
=7.5×(200-1),
=7.5×200-7.5×1,
=1500-7.5,
=1492.5;
(117)(+)×36
=×36,
=4+3,
=7;
(118)1.2×5.7-1.2+5.3×1.2
=(5.7+5.3-1)×1.2,
=10×1.2,
=12;
(119)0.825×102-82.5
=0.825×102-0.825×100,
=0.825×(102-100),
=0.825×2,
=1.65;
(120)46×=;
(121)560÷16÷5
=560÷(16×5),
=560÷80,
=7;
(122)3÷2.5,
=1.2;
(123)84+(54-16)
=84+38,
=122;
(124)+++
=(+)+(+),
=1+1,
=2;
(125)-(÷+)
=--,
=1-,
=;
(126)3×(+)+
=3×,
=(),
=1+,
=1;
(127)7.2÷(5-0.75+0.25)
=7.2÷4.5,
=1.6;
(128)725÷25+275÷25
=(725+275)÷25,
=1000÷25,
=40;
(129)××
=××,
=,
=;
(130)×45-÷
=×45-×45,
=0;
(131)48×(-)
=48×,
=40-18,
=22;
(132)×+×
=,
=;
(133)(32+)÷4
=32×,
=8+,
=8;
(134)÷÷
=,
=1;
(135)46×,
=(45+1)×,
=45×+;
=2;
(136)×+÷9
=()×,
=1×,
=.
分析:本题按照先算乘除再算加减,有括号的先算括号里面的顺序运算.注意观察算式的特点,能运用运算定律简算,或者其它简便方法简算的要简算.
点评:本题是考察的基本运算法则,根据运算顺序计算.本题有很多可以简算,用相关的运算定律简算.
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