a) 50 : (5 × 2) = 50 :10 = 5

50 : (5 × 2) = 50 : 5 : 2 = 5

b) 28 : (2 × 7) = 28 : 14 = 2

28 : (2 × 7) = 28 : 2 : 7

= 14 : 7 = 2

=(0,25x4)x(0,2x50)

=1x10

=10

\(0,25.0,2.4.50=\dfrac{1}{4}.\dfrac{1}{5}.4.50\)

                       \(=\left(\dfrac{1}{4}.4\right)\left(\dfrac{1}{5}.50\right)\)

                        \(=1.10\)

                         \(=10\)

\(0,25\times0,2\times4\times50\)

\(=\left(0,25\times4\right)\times\left(0,2\times50\right)\)

\(=1\times10\)

\(=10\)

Mk giải câu 1 nha

1) 2x - 3 = x + 1/2

➡️2x - x = 1/2 + 3

➡️x        = 7/2

Hok tốt~

3/5x7/9 - 3/5 x 2/9=3/5x(7/9+2/9)=3/5x1=3/5

Ai tích mk mk sẽ tích lại     

mình k rồi

10 x 5 + 5 x 10

c1 : 10 x (5 + 5)

        = 10 x 10

        = 100

c2 : (10 + 10) x 5 

       = 20 x 5

       = 100

50 + 10 + 90 + 50 + 30 + 60 + 10 + 70 + 50 + 50

c1 : (50 + 50) + (10 + 90) + (30 + 60 + 10) + (50 + 50) + 70

      =  100 + 100 + 100 + 100 + 70

      =   100 x 4 + 70

      = 400 + 70

      = 470

c2: 50 x 4 + (10 + 90) + (70 + 30) + (60 + 10)

     = 200 + 100 + 100 + 70

    = 200 + 100 x 2 + 70

    = 200 + 200 + 70

    = 200 x 2 + 70

     = 400 + 70 = 470

(450\(\times\)27):50

=12150:50

=243

(450 x 27) : 50

= (450 : 50) x 27

= 9 x 27

= 243

(45027):50

=(450:5)\(\times\)27

=90\(\times\)27

=2430