Áp dụng công thức này là được :

m.a+m.b+m.c = m(a+b+c)

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) 128.46 + 128.32 + 128.22

= 128.(46 + 32 + 22)

= 128. 100

= 12800

d) 12.35 + 35.182 - 35.94

= 35.(12 + 182 - 94)

= 35. 100

= 3500

e) 48.19 + 48.115 + 134.52

= 48.(19 + 115) + 134.52

= 48.134 + 134.52

= 134.(48 + 52)

= 134.100

= 13400

f) 136.23 + 136.17 - 40.36

= 136.(23 + 17) - 40.36

= 136.40 - 40.36

= 40.(136 - 36)

= 40.100

= 4000

g) 17.93 + 116.83 + 17.23

= 17.(93 + 23) + 116.83

= 17.116 + 116.83

= 116.(17 + 83)

= 116.100

= 11600

h) 19.27 + 47.81 + 19.20

= 19.(27 + 20) + 47.81

= 19.47 + 47.81

= 47.(19 + 81)

= 47.100

= 4700

i) 87.23 + 13.93 + 70.87

= 87.(23 + 70) + 13.93

= 87.93 + 13.93

= 93.(87 + 13)

= 93.100

= 9300

#NgHn

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

a,

58.75 + 58.50 - 58.25

= 58.(75 + 50 - 25)

= 58. (125 - 25)

= 58.100

 = 5800

b, 27.39 + 27.63 - 2.27

= 27.(39 + 63 - 2)

= 27.(102 - 2)

= 27.100

= 2700 

c, 128.46 + 128.32 + 128.22

= 128.(46 + 32 + 22)

= 128.(78 + 22)

= 128.100

= 12800

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)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)128.46+128.32+128.22

=128.(46+32+22)

=128.100

=12800

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) 128 . 46 + 128 . 32 + 128 . 22
= 128 . ( 46 + 32 + 22 )
= 128 . 100
= 12800
 

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)    128.46 + 128.32 +128.22 = 128(46 + 32 + 22) = 128.100 = 12800

58.75 + 58.50 - 58.25

= 58.(75 + 50 - 25)

= 58.100

= 5800

\(A=8\cdot17\cdot125=\left(125\cdot8\right)\cdot17=1000\cdot17=17000\)

\(B=\left(25\cdot4\right)\cdot37=100\cdot37=3700\)

\(C=\left(75+50-25\right)\cdot58=100\cdot58=5800\)

\(D=\left(39+63-2\right)\cdot27=100\cdot27=2700\)

A=8.17.125= (8.125).17= 1000.17=17000

b=4.37.25=(4.25).37=100.37=3700

c= 58.75+58.50-58.25= 58.(75+50 - 25)= 58.100=5800

d=27.39+27.63-2.27= 27.(39+63-2)=27.100=2700