1) Tính nhanh

a) Ta có: \(5\cdot79\cdot4\cdot2\cdot25\)

\(=\left(5\cdot2\right)\cdot\left(4\cdot25\right)\cdot79\)

\(=79\cdot10\cdot100\)

\(=79000\)

b) Ta có: \(27\cdot121-87\cdot27+73\cdot34\)

\(=27\cdot\left(121-87\right)+73\cdot34\)

\(=27\cdot34+73\cdot34\)

\(=34\cdot\left(27+73\right)\)

\(=34\cdot100=3400\)

a, 48.19 + 48.115 + 134.52

= 48 . ( 19 + 115 ) + 134.52

= 48 . 134 + 134 . 52

= 134 . ( 48 + 52 )

= 134 . 100

= 13400

b, 27 . 121 - 87 . 27 + 73 . 34

= 27 . ( 121 - 87 ) + 73 . 34

= 27 . 34 + 73 . 34

= 34 . ( 27 + 73 )

= 34 . 100

= 3400

a, 48 . 19 + 48 . 115 + 134 . 52

= 48 . ( 19 + 115 ) + 134 . 52

= 48 . 134 + 134 . 52

= ( 48 + 52 ) . 134

= 100 . 134

= 13400

b, 27 . 121 - 87 . 27 + 73 . 34

= 27 . ( 121 - 87 ) + 73 . 34

= 27 . 34 + 73 . 34

= ( 27 + 73 ) . 34

= 100 . 34

= 3400

1.a.48.19+48.115+134.52=48.(19+115)+134.52

=48.134+134.52

=134.(52+48)

=134.100=13400

1.b 27.121-87.27+73.34=27.(181-87)+73.34

=27.34+73.34

=(27+73).34

=100.34=3400

a)  48 . 19 + 48 . 115 + 134 . 52         b)  27 . 121 -  87 . 27 + 73 . 34        c)  29 . 38 - 29 . 23 + 64 . 71

  = 48 . ( 19 + 15 ) + 134 . 52               = 27 . ( 121 - 87 ) + 73 . 34              = 29 . ( 38 - 23 ) + 64 . 71

  = 48 . 134 + 134 . 52                          = 27 . 34 + 73 . 34                           = 29 .   15  + 64 . 71

  = 134 . ( 48 +52 )                               = 34 . ( 27 + 73 )                             =     4979

  = 134 . 100                                         = 34 .  100

  =    13400                                          =    3400

Phần c) mình thấy hơi sai sai đề , bạn xem lại đề nhé

a 58 x 75 + 58 x50 - 58 x25

= 58 x { 75 + 50 -25}

=58 x 100 

=5800

27 x 121 - 87 x27 +73x34

=27 x { 121 - 87 } + 73 x 34

=27 x 34 + 73 x34

= 34x { 27 + 37}

=27 x100

=2700

Cảm ơn các bạn nhiều

a) 58.75+58.50-58.25

= 58.(75+25-50)

= 58.50

= 2900

b) 27.121-87.27+73.34

= 27.(121-87)+73.34

= 27.34+73.34

= 34.(27+73)

= 34.100

= 3400

k mình nha

a,48.(19+115)+134.52=48.134+134.52=134.(48+52)=134.100=13400

b,27.(121-87)+73.364=27.34+73.34=34.(73+27)=34.100=3400

c,125.(98-46)-52.25=125.52-52.25=25.(125-25)=25.100=2500

tick nha

Bài 1

a) (3x - 2⁴).7³ = 2.7⁴

3x - 16 = 2.7⁴ : 7³

3x - 16 = 2.7

3x - 16 = 14

3x = 14 + 16

3x =30

x = 30 : 3

x = 10

b) x - [42 + (-28)] = -8

x - 14 = -8

x = -8 + 14

x = 6

c) 4 - 7.x = x - (13 - 4)

x + 7x = 4 + 9

8x = 13

x = 13/8

Bài 1: a,   (3\(x\) - 2⁴ ).7³ = 2.7⁴

                3\(x\) - 2⁴    = 2.7⁴ : 7³

                3\(x\)  - 16   = 14

                 3\(x\)           = 30 

                    \(x\)          = 10

b, \(x\) - (42 + (-28) ] = -8

    \(x\) - 14 = -8

    \(x\)        = 14 - 8

    \(x\)        = 6

c, 4 - (7\(x\)) = \(x\) - (13 - 4)

   4 - 7\(x\)   = \(x\) - 9

        \(x\) + 7\(x\) = 4 + 9

          8\(x\)     = 13

             \(x\)    = \(\dfrac{13}{8}\)

Bài 2

a) 58.75 + 58.50 - 58.25

= 58.(75 + 50 - 25)

= 58.100

= 5800

b) 27.39 + 27.63 - 2.27

= 27.(39 + 63 - 2)

= 27.100

= 2700

c) 48.13 + 48.115 + 134.52

= 48.(13 + 115) + 134.52

= 48.128 + 134.52

= 6144 + 6968

= 13112

d) 27.121 - 87.27 + 73.34

= 27.(121 - 87) + 73.34

= 27.34 + 73.34

= 34.(27 + 73)

= 27.100

= 2700

a) 48.19+48.115+134.52

=48.(19+115)+134.52

=48.134+134.52

=(48+52).134

=100.134

=13400

b) 27.121-87.27+73.34

=27.(121-87)+73.34

=27.34+73.34

=(27+73).34

=100.34

=3400

c)125.98-125.46-52.25

=125.(98-46)-52.25

=125.52-52.25

=(125-25).52

=100.52

=5200

d) 136.23+136.17-40.36

=136.(23+17)-40.36

=136.40-40.36

=(136-36).40

=100.40

=4000

e) 17.93+116.83+17.23

=17.(93+23)+116.83

=17.116+116.83

=(17+83).116

=100.83

=3800

ê)19.27+47.81+19.20

=19.(27+20)+47.81

=19.47+47.81

=(19+81).47

=100.47

=4700

f) 87.23+13.93+70.87

=87.(23+70)+13.93

=87.93+13.93

=(87+13).93

=100.93

=9300

câu e) sai rồi phải là 100.116=11600 mới đúng . Chúc bạn học tốt , yêu bạn nhiều

Trương Huy Tâm sai ròi

a, 5800

b, 2700

c, 12800

d, 5082

e, 10080

f, 13400

g, 5020

h, 5200

a) 29.75.2+58.50-58.25 b) 9.39.3+27.63-2.27

= (29.2).75+58.50-58.25 = (9.3).39+27.63-2.27

= 58.75+58.50-58.25 = 27.39+27.63-2.27

= 58.(75+50-25) = 27.(39+63-2)

= 58.100 = 27.100

= 5800. = 2700.

c)64.46.2+16.32.8+128.22 d)6.25.11+5.22.3+66.14+33.66

= (64.2).46+(16.8).32+128.22 = (6.11).25+5.(22.3)+66.14+33.66

= 128.46+128.32+128.22 = 66.25+5.66+66.14+33.66

= 128.(46+32+22) = 66.(25+5+14+33)

= 128.100 = 66.77

= 12800. = 5082

a) 29 . 75 . 2 + 58 . 50 - 58 . 25

= (29 . 2) . 75 + 58 . 50 - 58 . 25

= 58 . 75 + 58 . 50 - 58 . 25

= 58 . (75 + 50 - 25)

= 58 . (125 - 25)

= 58 . 100

= 5800

b) 9 . 39 . 3 + 27 . 63 - 2 . 27

= (9 . 3) . 39 + 27 . 63 - 2 . 27

= 27 . 39 + 27 . 63 - 2 . 27

= 27 . (39 + 63 - 2)

= 27 . (102 - 2)

= 27 . 100

= 2700

c) 64 . 46 . 2 + 16 . 32 . 8 + 128 . 22

= (64 . 2) . 46 + (16 . 8) . 32 + 128 . 22

= 128 . 46 + 128 . 32 + 128 . 22

= 128 . (46 + 32 + 22)

= 128 . (78 + 22)

= 128 . 100

= 12800

d) 6 . 25 . 11 + 5 . 22 . 3 + 66 . 14 + 33 . 66

= (6 . 11) . 25 + 5 . (22 . 3) + 66 . 14 + 33 .66

= 66 . 25 + 5 . 66 + 66 . 14 + 33 .66

= 66 . (25 + 5 + 14 + 33)

= 66 . (30 + 14 + 33)

= 66 . (44 + 33)

= 66 . 77

= 5082

e) 12 . 35 + 35 . 182 - 35 . 94

= 35 . (12 + 128 - 94)

= 35 . (140 - 94)

= 35 . 46

= 1610

f) 48 . 19 + 48 . 115 + 134 . 52

= 48 . (19 + 115) + 134 . 52

= 48 . 134 + 134 . 52

= 134 . (48 + 52)

= 134 . 100

= 13400

g) 27 . 121 - 87 . 27 + 73 . 34

= 27 . (121 - 87) + 73 . 34

= 27 . 34 + 73 . 34

= (27 + 73) . 34

= 100 . 34

= 3400

h) 125 . 98 - 125 . 46 - 52 . 25

= 125 . (98 - 46) - 52 . 25

= 125 . 52 - 52 . 25

= (125 - 25) . 52

= 100 . 52

= 5200